]> git.ipfire.org Git - thirdparty/Python/cpython.git/commitdiff
initial checkin of www Tk examples
authorGuido van Rossum <guido@python.org>
Tue, 10 Jan 1995 17:05:37 +0000 (17:05 +0000)
committerGuido van Rossum <guido@python.org>
Tue, 10 Jan 1995 17:05:37 +0000 (17:05 +0000)
18 files changed:
Demo/tkinter/www/Para.py [new file with mode: 0755]
Demo/tkinter/www/fmt.py [new file with mode: 0755]
Demo/tkinter/www/htmllib.py [new file with mode: 0755]
Demo/tkinter/www/sgmllib.py [new file with mode: 0755]
Demo/tkinter/www/tkfmt.py [new file with mode: 0755]
Demo/tkinter/www/www1.py [new file with mode: 0755]
Demo/tkinter/www/www10.py [new file with mode: 0755]
Demo/tkinter/www/www11.py [new file with mode: 0755]
Demo/tkinter/www/www12.py [new file with mode: 0755]
Demo/tkinter/www/www13.py [new file with mode: 0755]
Demo/tkinter/www/www2.py [new file with mode: 0755]
Demo/tkinter/www/www3.py [new file with mode: 0755]
Demo/tkinter/www/www4.py [new file with mode: 0755]
Demo/tkinter/www/www5.py [new file with mode: 0755]
Demo/tkinter/www/www6.py [new file with mode: 0755]
Demo/tkinter/www/www7.py [new file with mode: 0755]
Demo/tkinter/www/www8.py [new file with mode: 0755]
Demo/tkinter/www/www9.py [new file with mode: 0755]

diff --git a/Demo/tkinter/www/Para.py b/Demo/tkinter/www/Para.py
new file mode 100755 (executable)
index 0000000..6a7057d
--- /dev/null
@@ -0,0 +1,408 @@
+# Text formatting abstractions
+
+
+# Oft-used type object
+Int = type(0)
+
+
+# Represent a paragraph.  This is a list of words with associated
+# font and size information, plus indents and justification for the
+# entire paragraph.
+# Once the words have been added to a paragraph, it can be laid out
+# for different line widths.  Once laid out, it can be rendered at
+# different screen locations.  Once rendered, it can be queried
+# for mouse hits, and parts of the text can be highlighted
+class Para:
+       #
+       def __init__(self):
+               self.words = [] # The words
+               self.just = 'l' # Justification: 'l', 'r', 'lr' or 'c'
+               self.indent_left = self.indent_right = self.indent_hang = 0
+               # Final lay-out parameters, may change
+               self.left = self.top = self.right = self.bottom = \
+                       self.width = self.height = self.lines = None
+       #
+       # Add a word, computing size information for it.
+       # Words may also be added manually by appending to self.words
+       # Each word should be a 7-tuple:
+       # (font, text, width, space, stretch, ascent, descent)
+       def addword(self, d, font, text, space, stretch):
+               if font <> None:
+                       d.setfont(font)
+               width = d.textwidth(text)
+               ascent = d.baseline()
+               descent = d.lineheight() - ascent
+               spw = d.textwidth(' ')
+               space = space * spw
+               stretch = stretch * spw
+               tuple = (font, text, width, space, stretch, ascent, descent)
+               self.words.append(tuple)
+       #
+       # Hooks to begin and end anchors -- insert numbers in the word list!
+       def bgn_anchor(self, id):
+               self.words.append(id)
+       #
+       def end_anchor(self, id):
+               self.words.append(0)
+       #
+       # Return the total length (width) of the text added so far, in pixels
+       def getlength(self):
+               total = 0
+               for word in self.words:
+                       if type(word) <> Int:
+                               total = total + word[2] + word[3]
+               return total
+       #
+       # Tab to a given position (relative to the current left indent):
+       # remove all stretch, add fixed space up to the new indent.
+       # If the current position is already beying the tab stop,
+       # don't add any new space (but still remove the stretch)
+       def tabto(self, tab):
+               total = 0
+               as, de = 1, 0
+               for i in range(len(self.words)):
+                       word = self.words[i]
+                       if type(word) == Int: continue
+                       fo, te, wi, sp, st, as, de = word
+                       self.words[i] = fo, te, wi, sp, 0, as, de
+                       total = total + wi + sp
+               if total < tab:
+                       self.words.append(None, '', 0, tab-total, 0, as, de)
+       #
+       # Make a hanging tag: tab to hang, increment indent_left by hang,
+       # and reset indent_hang to -hang
+       def makehangingtag(self, hang):
+               self.tabto(hang)
+               self.indent_left = self.indent_left + hang
+               self.indent_hang = -hang
+       #
+       # Decide where the line breaks will be given some screen width
+       def layout(self, linewidth):
+               self.width = linewidth
+               height = 0
+               self.lines = lines = []
+               avail1 = self.width - self.indent_left - self.indent_right
+               avail = avail1 - self.indent_hang
+               words = self.words
+               i = 0
+               n = len(words)
+               lastfont = None
+               while i < n:
+                       firstfont = lastfont
+                       charcount = 0
+                       width = 0
+                       stretch = 0
+                       ascent = 0
+                       descent = 0
+                       lsp = 0
+                       j = i
+                       while i < n:
+                               word = words[i]
+                               if type(word) == Int:
+                                       if word > 0 and width >= avail:
+                                               break
+                                       i = i+1
+                                       continue
+                               fo, te, wi, sp, st, as, de = word
+                               if width + wi > avail and width > 0 and wi > 0:
+                                       break
+                               if fo <> None:
+                                       lastfont = fo
+                                       if width == 0:
+                                               firstfont = fo
+                               charcount = charcount + len(te) + (sp > 0)
+                               width = width + wi + sp
+                               lsp = sp
+                               stretch = stretch + st
+                               lst = st
+                               ascent = max(ascent, as)
+                               descent = max(descent, de)
+                               i = i+1
+                       while i > j and type(words[i-1]) == Int and \
+                               words[i-1] > 0: i = i-1
+                       width = width - lsp
+                       if i < n:
+                               stretch = stretch - lst
+                       else:
+                               stretch = 0
+                       tuple = i-j, firstfont, charcount, width, stretch, \
+                               ascent, descent
+                       lines.append(tuple)
+                       height = height + ascent + descent
+                       avail = avail1
+               self.height = height
+       #
+       # Call a function for all words in a line
+       def visit(self, wordfunc, anchorfunc):
+               avail1 = self.width - self.indent_left - self.indent_right
+               avail = avail1 - self.indent_hang
+               v = self.top
+               i = 0
+               for tuple in self.lines:
+                       wordcount, firstfont, charcount, width, stretch, \
+                               ascent, descent = tuple
+                       h = self.left + self.indent_left
+                       if i == 0: h = h + self.indent_hang
+                       extra = 0
+                       if self.just == 'r': h = h + avail - width
+                       elif self.just == 'c': h = h + (avail - width) / 2
+                       elif self.just == 'lr' and stretch > 0:
+                               extra = avail - width
+                       v2 = v + ascent + descent
+                       for j in range(i, i+wordcount):
+                               word = self.words[j]
+                               if type(word) == Int:
+                                       ok = anchorfunc(self, tuple, word, \
+                                                       h, v)
+                                       if ok <> None: return ok
+                                       continue
+                               fo, te, wi, sp, st, as, de = word
+                               if extra > 0 and stretch > 0:
+                                       ex = extra * st / stretch
+                                       extra = extra - ex
+                                       stretch = stretch - st
+                               else:
+                                       ex = 0
+                               h2 = h + wi + sp + ex
+                               ok = wordfunc(self, tuple, word, h, v, \
+                                       h2, v2, (j==i), (j==i+wordcount-1))
+                               if ok <> None: return ok
+                               h = h2
+                       v = v2
+                       i = i + wordcount
+                       avail = avail1
+       #
+       # Render a paragraph in "drawing object" d, using the rectangle
+       # given by (left, top, right) with an unspecified bottom.
+       # Return the computed bottom of the text.
+       def render(self, d, left, top, right):
+               if self.width <> right-left:
+                       self.layout(right-left)
+               self.left = left
+               self.top = top
+               self.right = right
+               self.bottom = self.top + self.height
+               self.anchorid = 0
+               try:
+                       self.d = d
+                       self.visit(self.__class__._renderword, \
+                                  self.__class__._renderanchor)
+               finally:
+                       self.d = None
+               return self.bottom
+       #
+       def _renderword(self, tuple, word, h, v, h2, v2, isfirst, islast):
+               if word[0] <> None: self.d.setfont(word[0])
+               baseline = v + tuple[5]
+               self.d.text((h, baseline - word[5]), word[1])
+               if self.anchorid > 0:
+                       self.d.line((h, baseline+2), (h2, baseline+2))
+       #
+       def _renderanchor(self, tuple, word, h, v):
+               self.anchorid = word
+       #
+       # Return which anchor(s) was hit by the mouse
+       def hitcheck(self, mouseh, mousev):
+               self.mouseh = mouseh
+               self.mousev = mousev
+               self.anchorid = 0
+               self.hits = []
+               self.visit(self.__class__._hitcheckword, \
+                          self.__class__._hitcheckanchor)
+               return self.hits
+       #
+       def _hitcheckword(self, tuple, word, h, v, h2, v2, isfirst, islast):
+               if self.anchorid > 0 and h <= self.mouseh <= h2 and \
+                       v <= self.mousev <= v2:
+                       self.hits.append(self.anchorid)
+       #
+       def _hitcheckanchor(self, tuple, word, h, v):
+               self.anchorid = word
+       #
+       # Return whether the given anchor id is present
+       def hasanchor(self, id):
+               return id in self.words or -id in self.words
+       #
+       # Extract the raw text from the word list, substituting one space
+       # for non-empty inter-word space, and terminating with '\n'
+       def extract(self):
+               text = ''
+               for w in self.words:
+                       if type(w) <> Int:
+                               word = w[1]
+                               if w[3]: word = word + ' '
+                               text = text + word
+               return text + '\n'
+       #
+       # Return which character position was hit by the mouse, as
+       # an offset in the entire text as returned by extract().
+       # Return None if the mouse was not in this paragraph
+       def whereis(self, d, mouseh, mousev):
+               if mousev < self.top or mousev > self.bottom:
+                       return None
+               self.mouseh = mouseh
+               self.mousev = mousev
+               self.lastfont = None
+               self.charcount = 0
+               try:
+                       self.d = d
+                       return self.visit(self.__class__._whereisword, \
+                                         self.__class__._whereisanchor)
+               finally:
+                       self.d = None
+       #
+       def _whereisword(self, tuple, word, h1, v1, h2, v2, isfirst, islast):
+               fo, te, wi, sp, st, as, de = word
+               if fo <> None: self.lastfont = fo
+               h = h1
+               if isfirst: h1 = 0
+               if islast: h2 = 999999
+               if not (v1 <= self.mousev <= v2 and h1 <= self.mouseh <= h2):
+                       self.charcount = self.charcount + len(te) + (sp > 0)
+                       return
+               if self.lastfont <> None:
+                       self.d.setfont(self.lastfont)
+               cc = 0
+               for c in te:
+                       cw = self.d.textwidth(c)
+                       if self.mouseh <= h + cw/2:
+                               return self.charcount + cc
+                       cc = cc+1
+                       h = h+cw
+               self.charcount = self.charcount + cc
+               if self.mouseh <= (h+h2) / 2:
+                       return self.charcount
+               else:
+                       return self.charcount + 1
+       #
+       def _whereisanchor(self, tuple, word, h, v):
+               pass
+       #
+       # Return screen position corresponding to position in paragraph.
+       # Return tuple (h, vtop, vbaseline, vbottom).
+       # This is more or less the inverse of whereis()
+       def screenpos(self, d, pos):
+               if pos < 0:
+                       ascent, descent = self.lines[0][5:7]
+                       return self.left, self.top, self.top + ascent, \
+                               self.top + ascent + descent
+               self.pos = pos
+               self.lastfont = None
+               try:
+                       self.d = d
+                       ok = self.visit(self.__class__._screenposword, \
+                                       self.__class__._screenposanchor)
+               finally:
+                       self.d = None
+               if ok == None:
+                       ascent, descent = self.lines[-1][5:7]
+                       ok = self.right, self.bottom - ascent - descent, \
+                               self.bottom - descent, self.bottom
+               return ok
+       #
+       def _screenposword(self, tuple, word, h1, v1, h2, v2, isfirst, islast):
+               fo, te, wi, sp, st, as, de = word
+               if fo <> None: self.lastfont = fo
+               cc = len(te) + (sp > 0)
+               if self.pos > cc:
+                       self.pos = self.pos - cc
+                       return
+               if self.pos < cc:
+                       self.d.setfont(self.lastfont)
+                       h = h1 + self.d.textwidth(te[:self.pos])
+               else:
+                       h = h2
+               ascent, descent = tuple[5:7]
+               return h, v1, v1+ascent, v2
+       #
+       def _screenposanchor(self, tuple, word, h, v):
+               pass
+       #
+       # Invert the stretch of text between pos1 and pos2.
+       # If pos1 is None, the beginning is implied;
+       # if pos2 is None, the end is implied.
+       # Undoes its own effect when called again with the same arguments
+       def invert(self, d, pos1, pos2):
+               if pos1 == None:
+                       pos1 = self.left, self.top, self.top, self.top
+               else:
+                       pos1 = self.screenpos(d, pos1)
+               if pos2 == None:
+                       pos2 = self.right, self.bottom,self.bottom,self.bottom
+               else:
+                       pos2 = self.screenpos(d, pos2)
+               h1, top1, baseline1, bottom1 = pos1
+               h2, top2, baseline2, bottom2 = pos2
+               if bottom1 <= top2:
+                       d.invert((h1, top1), (self.right, bottom1))
+                       h1 = self.left
+                       if bottom1 < top2:
+                               d.invert((h1, bottom1), (self.right, top2))
+                       top1, bottom1 = top2, bottom2
+               d.invert((h1, top1), (h2, bottom2))
+
+
+# Test class Para
+# XXX This was last used on the Mac, hence the weird fonts...
+def test():
+       import stdwin
+       from stdwinevents import *
+       words = 'The', 'quick', 'brown', 'fox', 'jumps', 'over', \
+               'the', 'lazy', 'dog.'
+       paralist = []
+       for just in 'l', 'r', 'lr', 'c':
+               p = Para()
+               p.just = just
+               p.addword(stdwin, ('New York', 'p', 12), words[0], 1, 1)
+               for word in words[1:-1]:
+                       p.addword(stdwin, None, word, 1, 1)
+               p.addword(stdwin, None, words[-1], 2, 4)
+               p.addword(stdwin, ('New York', 'b', 18), 'Bye!', 0, 0)
+               p.addword(stdwin, ('New York', 'p', 10), 'Bye!', 0, 0)
+               paralist.append(p)
+       window = stdwin.open('Para.test()')
+       start = stop = selpara = None
+       while 1:
+               etype, win, detail = stdwin.getevent()
+               if etype == WE_CLOSE:
+                       break
+               if etype == WE_SIZE:
+                       window.change((0, 0), (1000, 1000))
+               if etype == WE_DRAW:
+                       width, height = window.getwinsize()
+                       d = None
+                       try:
+                               d = window.begindrawing()
+                               d.cliprect(detail)
+                               d.erase(detail)
+                               v = 0
+                               for p in paralist:
+                                       v = p.render(d, 0, v, width)
+                                       if p == selpara and \
+                                          start <> None and stop <> None:
+                                               p.invert(d, start, stop)
+                       finally:
+                               if d: d.close()
+               if etype == WE_MOUSE_DOWN:
+                       if selpara and start <> None and stop <> None:
+                               d = window.begindrawing()
+                               selpara.invert(d, start, stop)
+                               d.close()
+                       start = stop = selpara = None
+                       mouseh, mousev = detail[0]
+                       for p in paralist:
+                               start = p.whereis(stdwin, mouseh, mousev)
+                               if start <> None:
+                                       selpara = p
+                                       break
+               if etype == WE_MOUSE_UP and start <> None and selpara:
+                       mouseh, mousev = detail[0]
+                       stop = selpara.whereis(stdwin, mouseh, mousev)
+                       if stop == None: start = selpara = None
+                       else:
+                               if start > stop:
+                                       start, stop = stop, start
+                               d = window.begindrawing()
+                               selpara.invert(d, start, stop)
+                               d.close()
+       window.close()
diff --git a/Demo/tkinter/www/fmt.py b/Demo/tkinter/www/fmt.py
new file mode 100755 (executable)
index 0000000..b5ca33c
--- /dev/null
@@ -0,0 +1,627 @@
+# Text formatting abstractions
+
+
+import string
+import Para
+
+
+# A formatter back-end object has one method that is called by the formatter:
+# addpara(p), where p is a paragraph object.  For example:
+
+
+# Formatter back-end to do nothing at all with the paragraphs
+class NullBackEnd:
+       #
+       def __init__(self):
+               pass
+       #
+       def addpara(self, p):
+               pass
+       #
+       def bgn_anchor(self, id):
+               pass
+       #
+       def end_anchor(self, id):
+               pass
+
+
+# Formatter back-end to collect the paragraphs in a list
+class SavingBackEnd(NullBackEnd):
+       #
+       def __init__(self):
+               self.paralist = []
+       #
+       def addpara(self, p):
+               self.paralist.append(p)
+       #
+       def hitcheck(self, h, v):
+               hits = []
+               for p in self.paralist:
+                       if p.top <= v <= p.bottom:
+                               for id in p.hitcheck(h, v):
+                                       if id not in hits:
+                                               hits.append(id)
+               return hits
+       #
+       def extract(self):
+               text = ''
+               for p in self.paralist:
+                       text = text + (p.extract())
+               return text
+       #
+       def extractpart(self, long1, long2):
+               if long1 > long2: long1, long2 = long2, long1
+               para1, pos1 = long1
+               para2, pos2 = long2
+               text = ''
+               while para1 < para2:
+                       ptext = self.paralist[para1].extract()
+                       text = text + ptext[pos1:]
+                       pos1 = 0
+                       para1 = para1 + 1
+               ptext = self.paralist[para2].extract()
+               return text + ptext[pos1:pos2]
+       #
+       def whereis(self, d, h, v):
+               total = 0
+               for i in range(len(self.paralist)):
+                       p = self.paralist[i]
+                       result = p.whereis(d, h, v)
+                       if result <> None:
+                               return i, result
+               return None
+       #
+       def roundtowords(self, long1, long2):
+               i, offset = long1
+               text = self.paralist[i].extract()
+               while offset > 0 and text[offset-1] <> ' ': offset = offset-1
+               long1 = i, offset
+               #
+               i, offset = long2
+               text = self.paralist[i].extract()
+               n = len(text)
+               while offset < n-1 and text[offset] <> ' ': offset = offset+1
+               long2 = i, offset
+               #
+               return long1, long2
+       #
+       def roundtoparagraphs(self, long1, long2):
+               long1 = long1[0], 0
+               long2 = long2[0], len(self.paralist[long2[0]].extract())
+               return long1, long2
+
+
+# Formatter back-end to send the text directly to the drawing object
+class WritingBackEnd(NullBackEnd):
+       #
+       def __init__(self, d, width):
+               self.d = d
+               self.width = width
+               self.lineno = 0
+       #
+       def addpara(self, p):
+               self.lineno = p.render(self.d, 0, self.lineno, self.width)
+
+
+# A formatter receives a stream of formatting instructions and assembles
+# these into a stream of paragraphs on to a back-end.  The assembly is
+# parametrized by a text measurement object, which must match the output
+# operations of the back-end.  The back-end is responsible for splitting
+# paragraphs up in lines of a given maximum width.  (This is done because
+# in a windowing environment, when the window size changes, there is no
+# need to redo the assembly into paragraphs, but the splitting into lines
+# must be done taking the new window size into account.)
+
+
+# Formatter base class.  Initialize it with a text measurement object,
+# which is used for text measurements, and a back-end object,
+# which receives the completed paragraphs.  The formatting methods are:
+# setfont(font)
+# setleftindent(nspaces)
+# setjust(type) where type is 'l', 'c', 'r', or 'lr'
+# flush()
+# vspace(nlines)
+# needvspace(nlines)
+# addword(word, nspaces)
+class BaseFormatter:
+       #
+       def __init__(self, d, b):
+               # Drawing object used for text measurements
+               self.d = d
+               #
+               # BackEnd object receiving completed paragraphs
+               self.b = b
+               #
+               # Parameters of the formatting model
+               self.leftindent = 0
+               self.just = 'l'
+               self.font = None
+               self.blanklines = 0
+               #
+               # Parameters derived from the current font
+               self.space = d.textwidth(' ')
+               self.line = d.lineheight()
+               self.ascent = d.baseline()
+               self.descent = self.line - self.ascent
+               #
+               # Parameter derived from the default font
+               self.n_space = self.space
+               #
+               # Current paragraph being built
+               self.para = None
+               self.nospace = 1
+               #
+               # Font to set on the next word
+               self.nextfont = None
+       #
+       def newpara(self):
+               return Para.Para()
+       #
+       def setfont(self, font):
+               if font == None: return
+               self.font = self.nextfont = font
+               d = self.d
+               d.setfont(font)
+               self.space = d.textwidth(' ')
+               self.line = d.lineheight()
+               self.ascent = d.baseline()
+               self.descent = self.line - self.ascent
+       #
+       def setleftindent(self, nspaces):
+               self.leftindent = int(self.n_space * nspaces)
+               if self.para:
+                       hang = self.leftindent - self.para.indent_left
+                       if hang > 0 and self.para.getlength() <= hang:
+                               self.para.makehangingtag(hang)
+                               self.nospace = 1
+                       else:
+                               self.flush()
+       #
+       def setrightindent(self, nspaces):
+               self.rightindent = int(self.n_space * nspaces)
+               if self.para:
+                       self.para.indent_right = self.rightindent
+                       self.flush()
+       #
+       def setjust(self, just):
+               self.just = just
+               if self.para:
+                       self.para.just = self.just
+       #
+       def flush(self):
+               if self.para:
+                       self.b.addpara(self.para)
+                       self.para = None
+                       if self.font <> None:
+                               self.d.setfont(self.font)
+               self.nospace = 1
+       #
+       def vspace(self, nlines):
+               self.flush()
+               if nlines > 0:
+                       self.para = self.newpara()
+                       tuple = None, '', 0, 0, 0, int(nlines*self.line), 0
+                       self.para.words.append(tuple)
+                       self.flush()
+                       self.blanklines = self.blanklines + nlines
+       #
+       def needvspace(self, nlines):
+               self.flush() # Just to be sure
+               if nlines > self.blanklines:
+                       self.vspace(nlines - self.blanklines)
+       #
+       def addword(self, text, space):
+               if self.nospace and not text:
+                       return
+               self.nospace = 0
+               self.blanklines = 0
+               if not self.para:
+                       self.para = self.newpara()
+                       self.para.indent_left = self.leftindent
+                       self.para.just = self.just
+                       self.nextfont = self.font
+               space = int(space * self.space)
+               self.para.words.append(self.nextfont, text, \
+                       self.d.textwidth(text), space, space, \
+                       self.ascent, self.descent)
+               self.nextfont = None
+       #
+       def bgn_anchor(self, id):
+               if not self.para:
+                       self.nospace = 0
+                       self.addword('', 0)
+               self.para.bgn_anchor(id)
+       #
+       def end_anchor(self, id):
+               if not self.para:
+                       self.nospace = 0
+                       self.addword('', 0)
+               self.para.end_anchor(id)
+       #
+       def hrule(self):
+               # Typically need to override this for bit-mapped displays
+               self.flush()
+               self.addword('-'*60, 0)
+               self.flush()
+
+
+# Measuring object for measuring text as viewed on a tty
+class NullMeasurer:
+       #
+       def __init__(self):
+               pass
+       #
+       def setfont(self, font):
+               pass
+       #
+       def textwidth(self, text):
+               return len(text)
+       #
+       def lineheight(self):
+               return 1
+       #
+       def baseline(self):
+               return 0
+
+
+# Drawing object for writing plain ASCII text to a file
+class FileWriter:
+       #
+       def __init__(self, fp):
+               self.fp = fp
+               self.lineno, self.colno = 0, 0
+       #
+       def setfont(self, font):
+               pass
+       #
+       def text(self, (h, v), str):
+               if not str: return
+               if '\n' in str:
+                       raise ValueError, 'can\'t write \\n'
+               while self.lineno < v:
+                       self.fp.write('\n')
+                       self.colno, self.lineno = 0, self.lineno + 1
+               while self.lineno > v:
+                       # XXX This should never happen...
+                       self.fp.write('\033[A') # ANSI up arrow
+                       self.lineno = self.lineno - 1
+               if self.colno < h:
+                       self.fp.write(' ' * (h - self.colno))
+               elif self.colno > h:
+                       self.fp.write('\b' * (self.colno - h))
+               self.colno = h
+               self.fp.write(str)
+               self.colno = h + len(str)
+
+
+# Formatting class to do nothing at all with the data
+class NullFormatter(BaseFormatter):
+       #
+       def __init__(self):
+               d = NullMeasurer()
+               b = NullBackEnd()
+               BaseFormatter.__init__(self, d, b)
+
+
+# Formatting class to write directly to a file
+class WritingFormatter(BaseFormatter):
+       #
+       def __init__(self, fp, width):
+               dm = NullMeasurer()
+               dw = FileWriter(fp)
+               b = WritingBackEnd(dw, width)
+               BaseFormatter.__init__(self, dm, b)
+               self.blanklines = 1
+       #
+       # Suppress multiple blank lines
+       def needvspace(self, nlines):
+               BaseFormatter.needvspace(self, min(1, nlines))
+
+
+# A "FunnyFormatter" writes ASCII text with a twist: *bold words*,
+# _italic text_ and _underlined words_, and `quoted text'.
+# It assumes that the fonts are 'r', 'i', 'b', 'u', 'q': (roman,
+# italic, bold, underline, quote).
+# Moreover, if the font is in upper case, the text is converted to
+# UPPER CASE.
+class FunnyFormatter(WritingFormatter):
+       #
+       def flush(self):
+               if self.para: finalize(self.para)
+               WritingFormatter.flush(self)
+
+
+# Surrounds *bold words* and _italic text_ in a paragraph with
+# appropriate markers, fixing the size (assuming these characters'
+# width is 1).
+openchar = \
+    {'b':'*', 'i':'_', 'u':'_', 'q':'`', 'B':'*', 'I':'_', 'U':'_', 'Q':'`'}
+closechar = \
+    {'b':'*', 'i':'_', 'u':'_', 'q':'\'', 'B':'*', 'I':'_', 'U':'_', 'Q':'\''}
+def finalize(para):
+       oldfont = curfont = 'r'
+       para.words.append('r', '', 0, 0, 0, 0) # temporary, deleted at end
+       for i in range(len(para.words)):
+               fo, te, wi = para.words[i][:3]
+               if fo <> None: curfont = fo
+               if curfont <> oldfont:
+                       if closechar.has_key(oldfont):
+                               c = closechar[oldfont]
+                               j = i-1
+                               while j > 0 and para.words[j][1] == '': j = j-1
+                               fo1, te1, wi1 = para.words[j][:3]
+                               te1 = te1 + c
+                               wi1 = wi1 + len(c)
+                               para.words[j] = (fo1, te1, wi1) + \
+                                       para.words[j][3:]
+                       if openchar.has_key(curfont) and te:
+                               c = openchar[curfont]
+                               te = c + te
+                               wi = len(c) + wi
+                               para.words[i] = (fo, te, wi) + \
+                                       para.words[i][3:]
+                       if te: oldfont = curfont
+                       else: oldfont = 'r'
+               if curfont in string.uppercase:
+                       te = string.upper(te)
+                       para.words[i] = (fo, te, wi) + para.words[i][3:]
+       del para.words[-1]
+
+
+# Formatter back-end to draw the text in a window.
+# This has an option to draw while the paragraphs are being added,
+# to minimize the delay before the user sees anything.
+# This manages the entire "document" of the window.
+class StdwinBackEnd(SavingBackEnd):
+       #
+       def __init__(self, window, drawnow):
+               self.window = window
+               self.drawnow = drawnow
+               self.width = window.getwinsize()[0]
+               self.selection = None
+               self.height = 0
+               window.setorigin(0, 0)
+               window.setdocsize(0, 0)
+               self.d = window.begindrawing()
+               SavingBackEnd.__init__(self)
+       #
+       def finish(self):
+               self.d.close()
+               self.d = None
+               self.window.setdocsize(0, self.height)
+       #
+       def addpara(self, p):
+               self.paralist.append(p)
+               if self.drawnow:
+                       self.height = \
+                               p.render(self.d, 0, self.height, self.width)
+               else:
+                       p.layout(self.width)
+                       p.left = 0
+                       p.top = self.height
+                       p.right = self.width
+                       p.bottom = self.height + p.height
+                       self.height = p.bottom
+       #
+       def resize(self):
+               self.window.change((0, 0), (self.width, self.height))
+               self.width = self.window.getwinsize()[0]
+               self.height = 0
+               for p in self.paralist:
+                       p.layout(self.width)
+                       p.left = 0
+                       p.top = self.height
+                       p.right = self.width
+                       p.bottom = self.height + p.height
+                       self.height = p.bottom
+               self.window.change((0, 0), (self.width, self.height))
+               self.window.setdocsize(0, self.height)
+       #
+       def redraw(self, area):
+               d = self.window.begindrawing()
+               (left, top), (right, bottom) = area
+               d.erase(area)
+               d.cliprect(area)
+               for p in self.paralist:
+                       if top < p.bottom and p.top < bottom:
+                               v = p.render(d, p.left, p.top, p.right)
+               if self.selection:
+                       self.invert(d, self.selection)
+               d.close()
+       #
+       def setselection(self, new):
+               if new:
+                       long1, long2 = new
+                       pos1 = long1[:3]
+                       pos2 = long2[:3]
+                       new = pos1, pos2
+               if new <> self.selection:
+                       d = self.window.begindrawing()
+                       if self.selection:
+                               self.invert(d, self.selection)
+                       if new:
+                               self.invert(d, new)
+                       d.close()
+                       self.selection = new
+       #
+       def getselection(self):
+               return self.selection
+       #
+       def extractselection(self):
+               if self.selection:
+                       a, b = self.selection
+                       return self.extractpart(a, b)
+               else:
+                       return None
+       #
+       def invert(self, d, region):
+               long1, long2 = region
+               if long1 > long2: long1, long2 = long2, long1
+               para1, pos1 = long1
+               para2, pos2 = long2
+               while para1 < para2:
+                       self.paralist[para1].invert(d, pos1, None)
+                       pos1 = None
+                       para1 = para1 + 1
+               self.paralist[para2].invert(d, pos1, pos2)
+       #
+       def search(self, prog):
+               import regex, string
+               if type(prog) == type(''):
+                       prog = regex.compile(string.lower(prog))
+               if self.selection:
+                       iold = self.selection[0][0]
+               else:
+                       iold = -1
+               hit = None
+               for i in range(len(self.paralist)):
+                       if i == iold or i < iold and hit:
+                               continue
+                       p = self.paralist[i]
+                       text = string.lower(p.extract())
+                       if prog.search(text) >= 0:
+                               a, b = prog.regs[0]
+                               long1 = i, a
+                               long2 = i, b
+                               hit = long1, long2
+                               if i > iold:
+                                       break
+               if hit:
+                       self.setselection(hit)
+                       i = hit[0][0]
+                       p = self.paralist[i]
+                       self.window.show((p.left, p.top), (p.right, p.bottom))
+                       return 1
+               else:
+                       return 0
+       #
+       def showanchor(self, id):
+               for i in range(len(self.paralist)):
+                       p = self.paralist[i]
+                       if p.hasanchor(id):
+                               long1 = i, 0
+                               long2 = i, len(p.extract())
+                               hit = long1, long2
+                               self.setselection(hit)
+                               self.window.show( \
+                                       (p.left, p.top), (p.right, p.bottom))
+                               break
+
+
+# GL extensions
+
+class GLFontCache:
+       #
+       def __init__(self):
+               self.reset()
+               self.setfont('')
+       #
+       def reset(self):
+               self.fontkey = None
+               self.fonthandle = None
+               self.fontinfo = None
+               self.fontcache = {}
+       #
+       def close(self):
+               self.reset()
+       #
+       def setfont(self, fontkey):
+               if fontkey == '':
+                       fontkey = 'Times-Roman 12'
+               elif ' ' not in fontkey:
+                       fontkey = fontkey + ' 12'
+               if fontkey == self.fontkey:
+                       return
+               if self.fontcache.has_key(fontkey):
+                       handle = self.fontcache[fontkey]
+               else:
+                       import string
+                       i = string.index(fontkey, ' ')
+                       name, sizestr = fontkey[:i], fontkey[i:]
+                       size = eval(sizestr)
+                       key1 = name + ' 1'
+                       key = name + ' ' + `size`
+                       # NB key may differ from fontkey!
+                       if self.fontcache.has_key(key):
+                               handle = self.fontcache[key]
+                       else:
+                               if self.fontcache.has_key(key1):
+                                       handle = self.fontcache[key1]
+                               else:
+                                       import fm
+                                       handle = fm.findfont(name)
+                                       self.fontcache[key1] = handle
+                               handle = handle.scalefont(size)
+                               self.fontcache[fontkey] = \
+                                       self.fontcache[key] = handle
+               self.fontkey = fontkey
+               if self.fonthandle <> handle:
+                       self.fonthandle = handle
+                       self.fontinfo = handle.getfontinfo()
+                       handle.setfont()
+
+
+class GLMeasurer(GLFontCache):
+       #
+       def textwidth(self, text):
+               return self.fonthandle.getstrwidth(text)
+       #
+       def baseline(self):
+               return self.fontinfo[6] - self.fontinfo[3]
+       #
+       def lineheight(self):
+               return self.fontinfo[6]
+
+
+class GLWriter(GLFontCache):
+       #
+       # NOTES:
+       # (1) Use gl.ortho2 to use X pixel coordinates!
+       #
+       def text(self, (h, v), text):
+               import gl, fm
+               gl.cmov2i(h, v + self.fontinfo[6] - self.fontinfo[3])
+               fm.prstr(text)
+       #
+       def setfont(self, fontkey):
+               oldhandle = self.fonthandle
+               GLFontCache.setfont(fontkey)
+               if self.fonthandle <> oldhandle:
+                       handle.setfont()
+
+
+class GLMeasurerWriter(GLMeasurer, GLWriter):
+       pass
+
+
+class GLBackEnd(SavingBackEnd):
+       #
+       def __init__(self, wid):
+               import gl
+               gl.winset(wid)
+               self.wid = wid
+               self.width = gl.getsize()[1]
+               self.height = 0
+               self.d = GLMeasurerWriter()
+               SavingBackEnd.__init__(self)
+       #
+       def finish(self):
+               pass
+       #
+       def addpara(self, p):
+               self.paralist.append(p)
+               self.height = p.render(self.d, 0, self.height, self.width)
+       #
+       def redraw(self):
+               import gl
+               gl.winset(self.wid)
+               width = gl.getsize()[1]
+               if width <> self.width:
+                       setdocsize = 1
+                       self.width = width
+                       for p in self.paralist:
+                               p.top = p.bottom = None
+               d = self.d
+               v = 0
+               for p in self.paralist:
+                       v = p.render(d, 0, v, width)
diff --git a/Demo/tkinter/www/htmllib.py b/Demo/tkinter/www/htmllib.py
new file mode 100755 (executable)
index 0000000..f45657f
--- /dev/null
@@ -0,0 +1,639 @@
+# A parser for HTML documents
+
+
+# HTML: HyperText Markup Language; an SGML-like syntax used by WWW to
+# describe hypertext documents
+#
+# SGML: Standard Generalized Markup Language
+#
+# WWW: World-Wide Web; a distributed hypertext system develped at CERN
+#
+# CERN: European Particle Physics Laboratory in Geneva, Switzerland
+
+
+# This file is only concerned with parsing and formatting HTML
+# documents, not with the other (hypertext and networking) aspects of
+# the WWW project.  (It does support highlighting of anchors.)
+
+
+import os
+import sys
+import regex
+import string
+import sgmllib
+
+
+class HTMLParser(sgmllib.SGMLParser):
+
+       # Copy base class entities and add some
+       entitydefs = {}
+       for key in sgmllib.SGMLParser.entitydefs.keys():
+               entitydefs[key] = sgmllib.SGMLParser.entitydefs[key]
+       entitydefs['bullet'] = '*'
+
+       # Provided -- handlers for tags introducing literal text
+       
+       def start_listing(self, attrs):
+               self.setliteral('listing')
+               self.literal_bgn('listing', attrs)
+
+       def end_listing(self):
+               self.literal_end('listing')
+
+       def start_xmp(self, attrs):
+               self.setliteral('xmp')
+               self.literal_bgn('xmp', attrs)
+
+       def end_xmp(self):
+               self.literal_end('xmp')
+
+       def do_plaintext(self, attrs):
+               self.setnomoretags()
+               self.literal_bgn('plaintext', attrs)
+
+       # To be overridden -- begin/end literal mode
+       def literal_bgn(self, tag, attrs): pass
+       def literal_end(self, tag): pass
+
+
+# Next level of sophistication -- collect anchors, title, nextid and isindex
+class CollectingParser(HTMLParser):
+       #
+       def __init__(self):
+               HTMLParser.__init__(self)
+               self.savetext = None
+               self.nextid = ''
+               self.isindex = 0
+               self.title = ''
+               self.inanchor = 0
+               self.anchors = []
+               self.anchornames = []
+               self.anchortypes = []
+       #
+       def start_a(self, attrs):
+               self.inanchor = 0
+               href = ''
+               name = ''
+               type = ''
+               for attrname, value in attrs:
+                       if attrname == 'href':
+                               href = value
+                       if attrname == 'name=':
+                               name = value
+                       if attrname == 'type=':
+                               type = string.lower(value)
+               if not (href or name):
+                       return
+               self.anchors.append(href)
+               self.anchornames.append(name)
+               self.anchortypes.append(type)
+               self.inanchor = len(self.anchors)
+               if not href:
+                       self.inanchor = -self.inanchor
+       #
+       def end_a(self):
+               if self.inanchor > 0:
+                       # Don't show anchors pointing into the current document
+                       if self.anchors[self.inanchor-1][:1] <> '#':
+                               self.handle_data('[' + `self.inanchor` + ']')
+               self.inanchor = 0
+       #
+       def start_header(self, attrs): pass
+       def end_header(self): pass
+       #
+       # (head is the same as header)
+       def start_head(self, attrs): pass
+       def end_head(self): pass
+       #
+       def start_body(self, attrs): pass
+       def end_body(self): pass
+       #
+       def do_nextid(self, attrs):
+               self.nextid = attrs
+       #
+       def do_isindex(self, attrs):
+               self.isindex = 1
+       #
+       def start_title(self, attrs):
+               self.savetext = ''
+       #
+       def end_title(self):
+               if self.savetext <> None:
+                       self.title = self.savetext
+                       self.savetext = None
+       #
+       def handle_data(self, text):
+               if self.savetext is not None:
+                       self.savetext = self.savetext + text
+
+
+# Formatting parser -- takes a formatter and a style sheet as arguments
+
+# XXX The use of style sheets should change: for each tag and end tag
+# there should be a style definition, and a style definition should
+# encompass many more parameters: font, justification, indentation,
+# vspace before, vspace after, hanging tag...
+
+wordprog = regex.compile('[^ \t\n]*')
+spaceprog = regex.compile('[ \t\n]*')
+
+class FormattingParser(CollectingParser):
+
+       def __init__(self, formatter, stylesheet):
+               CollectingParser.__init__(self)
+               self.fmt = formatter
+               self.stl = stylesheet
+               self.savetext = None
+               self.compact = 0
+               self.nofill = 0
+               self.resetfont()
+               self.setindent(self.stl.stdindent)
+
+       def resetfont(self):
+               self.fontstack = []
+               self.stylestack = []
+               self.fontset = self.stl.stdfontset
+               self.style = ROMAN
+               self.passfont()
+
+       def passfont(self):
+               font = self.fontset[self.style]
+               self.fmt.setfont(font)
+
+       def pushstyle(self, style):
+               self.stylestack.append(self.style)
+               self.style = min(style, len(self.fontset)-1)
+               self.passfont()
+
+       def popstyle(self):
+               self.style = self.stylestack[-1]
+               del self.stylestack[-1]
+               self.passfont()
+
+       def pushfontset(self, fontset, style):
+               self.fontstack.append(self.fontset)
+               self.fontset = fontset
+               self.pushstyle(style)
+
+       def popfontset(self):
+               self.fontset = self.fontstack[-1]
+               del self.fontstack[-1]
+               self.popstyle()
+
+       def flush(self):
+               self.fmt.flush()
+
+       def setindent(self, n):
+               self.fmt.setleftindent(n)
+
+       def needvspace(self, n):
+               self.fmt.needvspace(n)
+
+       def close(self):
+               HTMLParser.close(self)
+               self.fmt.flush()
+
+       def handle_literal(self, text):
+               lines = string.splitfields(text, '\n')
+               for i in range(1, len(lines)):
+                       lines[i] = string.expandtabs(lines[i], 8)
+               for line in lines[:-1]:
+                       self.fmt.addword(line, 0)
+                       self.fmt.flush()
+                       self.fmt.nospace = 0
+               for line in lines[-1:]:
+                       self.fmt.addword(line, 0)
+
+       def handle_data(self, text):
+               if self.savetext is not None:
+                       self.savetext = self.savetext + text
+                       return
+               if self.literal:
+                       self.handle_literal(text)
+                       return
+               i = 0
+               n = len(text)
+               while i < n:
+                       j = i + wordprog.match(text, i)
+                       word = text[i:j]
+                       i = j + spaceprog.match(text, j)
+                       self.fmt.addword(word, i-j)
+                       if self.nofill and '\n' in text[j:i]:
+                               self.fmt.flush()
+                               self.fmt.nospace = 0
+                               i = j+1
+                               while text[i-1] <> '\n': i = i+1
+
+       def literal_bgn(self, tag, attrs):
+               if tag == 'plaintext':
+                       self.flush()
+               else:
+                       self.needvspace(1)
+               self.pushfontset(self.stl.stdfontset, FIXED)
+               self.setindent(self.stl.literalindent)
+
+       def literal_end(self, tag):
+               self.needvspace(1)
+               self.popfontset()
+               self.setindent(self.stl.stdindent)
+
+       def start_title(self, attrs):
+               self.flush()
+               self.savetext = ''
+       # NB end_title is unchanged
+
+       def do_p(self, attrs):
+               if self.compact:
+                       self.flush()
+               else:
+                       self.needvspace(1)
+
+       def do_hr(self, attrs):
+               self.fmt.hrule()
+
+       def start_h1(self, attrs):
+               self.needvspace(2)
+               self.setindent(self.stl.h1indent)
+               self.pushfontset(self.stl.h1fontset, BOLD)
+               self.fmt.setjust('c')
+
+       def end_h1(self):
+               self.popfontset()
+               self.needvspace(2)
+               self.setindent(self.stl.stdindent)
+               self.fmt.setjust('l')
+
+       def start_h2(self, attrs):
+               self.needvspace(1)
+               self.setindent(self.stl.h2indent)
+               self.pushfontset(self.stl.h2fontset, BOLD)
+
+       def end_h2(self):
+               self.popfontset()
+               self.needvspace(1)
+               self.setindent(self.stl.stdindent)
+
+       def start_h3(self, attrs):
+               self.needvspace(1)
+               self.setindent(self.stl.stdindent)
+               self.pushfontset(self.stl.h3fontset, BOLD)
+
+       def end_h3(self):
+               self.popfontset()
+               self.needvspace(1)
+               self.setindent(self.stl.stdindent)
+
+       def start_h4(self, attrs):
+               self.needvspace(1)
+               self.setindent(self.stl.stdindent)
+               self.pushfontset(self.stl.stdfontset, BOLD)
+
+       def end_h4(self):
+               self.popfontset()
+               self.needvspace(1)
+               self.setindent(self.stl.stdindent)
+
+       start_h5 = start_h4
+       end_h5 = end_h4
+
+       start_h6 = start_h5
+       end_h6 = end_h5
+
+       start_h7 = start_h6
+       end_h7 = end_h6
+
+       def start_ul(self, attrs):
+               self.needvspace(1)
+               for attrname, value in attrs:
+                       if attrname == 'compact':
+                               self.compact = 1
+                               self.setindent(0)
+                               break
+               else:
+                       self.setindent(self.stl.ulindent)
+
+       start_dir = start_menu = start_ol = start_ul
+
+       do_li = do_p
+
+       def end_ul(self):
+               self.compact = 0
+               self.needvspace(1)
+               self.setindent(self.stl.stdindent)
+
+       end_dir = end_menu = end_ol = end_ul
+
+       def start_dl(self, attrs):
+               for attrname, value in attrs:
+                       if attrname == 'compact':
+                               self.compact = 1
+               self.needvspace(1)
+
+       def end_dl(self):
+               self.compact = 0
+               self.needvspace(1)
+               self.setindent(self.stl.stdindent)
+
+       def do_dt(self, attrs):
+               if self.compact:
+                       self.flush()
+               else:
+                       self.needvspace(1)
+               self.setindent(self.stl.stdindent)
+
+       def do_dd(self, attrs):
+               self.fmt.addword('', 1)
+               self.setindent(self.stl.ddindent)
+
+       def start_address(self, attrs):
+               self.compact = 1
+               self.needvspace(1)
+               self.fmt.setjust('r')
+
+       def end_address(self):
+               self.compact = 0
+               self.needvspace(1)
+               self.setindent(self.stl.stdindent)
+               self.fmt.setjust('l')
+
+       def start_pre(self, attrs):
+               self.needvspace(1)
+               self.nofill = self.nofill + 1
+               self.pushstyle(FIXED)
+
+       def end_pre(self):
+               self.popstyle()
+               self.nofill = self.nofill - 1
+               self.needvspace(1)
+
+       start_typewriter = start_pre
+       end_typewriter = end_pre
+
+       def do_img(self, attrs):
+               self.fmt.addword('(image)', 0)
+
+       # Physical styles
+
+       def start_tt(self, attrs): self.pushstyle(FIXED)
+       def end_tt(self): self.popstyle()
+
+       def start_b(self, attrs): self.pushstyle(BOLD)
+       def end_b(self): self.popstyle()
+
+       def start_i(self, attrs): self.pushstyle(ITALIC)
+       def end_i(self): self.popstyle()
+
+       def start_u(self, attrs): self.pushstyle(ITALIC) # Underline???
+       def end_u(self): self.popstyle()
+
+       def start_r(self, attrs): self.pushstyle(ROMAN) # Not official
+       def end_r(self): self.popstyle()
+
+       # Logical styles
+
+       start_em = start_i
+       end_em = end_i
+
+       start_strong = start_b
+       end_strong = end_b
+
+       start_code = start_tt
+       end_code = end_tt
+
+       start_samp = start_tt
+       end_samp = end_tt
+
+       start_kbd = start_tt
+       end_kbd = end_tt
+
+       start_file = start_tt # unofficial
+       end_file = end_tt
+
+       start_var = start_i
+       end_var = end_i
+
+       start_dfn = start_i
+       end_dfn = end_i
+
+       start_cite = start_i
+       end_cite = end_i
+
+       start_hp1 = start_i
+       end_hp1 = start_i
+
+       start_hp2 = start_b
+       end_hp2 = end_b
+
+       def unknown_starttag(self, tag, attrs):
+               print '*** unknown <' + tag + '>'
+
+       def unknown_endtag(self, tag):
+               print '*** unknown </' + tag + '>'
+
+
+# An extension of the formatting parser which formats anchors differently.
+class AnchoringParser(FormattingParser):
+
+       def start_a(self, attrs):
+               FormattingParser.start_a(self, attrs)
+               if self.inanchor:
+                       self.fmt.bgn_anchor(self.inanchor)
+
+       def end_a(self):
+               if self.inanchor:
+                       self.fmt.end_anchor(self.inanchor)
+                       self.inanchor = 0
+
+
+# Style sheet -- this is never instantiated, but the attributes
+# of the class object itself are used to specify fonts to be used
+# for various paragraph styles.
+# A font set is a non-empty list of fonts, in the order:
+# [roman, italic, bold, fixed].
+# When a style is not available the nearest lower style is used
+
+ROMAN = 0
+ITALIC = 1
+BOLD = 2
+FIXED = 3
+
+class NullStylesheet:
+       # Fonts -- none
+       stdfontset = [None]
+       h1fontset = [None]
+       h2fontset = [None]
+       h3fontset = [None]
+       # Indents
+       stdindent = 2
+       ddindent = 25
+       ulindent = 4
+       h1indent = 0
+       h2indent = 0
+       literalindent = 0
+
+
+class X11Stylesheet(NullStylesheet):
+       stdfontset = [ \
+               '-*-helvetica-medium-r-normal-*-*-100-100-*-*-*-*-*', \
+               '-*-helvetica-medium-o-normal-*-*-100-100-*-*-*-*-*', \
+               '-*-helvetica-bold-r-normal-*-*-100-100-*-*-*-*-*', \
+               '-*-courier-medium-r-normal-*-*-100-100-*-*-*-*-*', \
+               ]
+       h1fontset = [ \
+               '-*-helvetica-medium-r-normal-*-*-180-100-*-*-*-*-*', \
+               '-*-helvetica-medium-o-normal-*-*-180-100-*-*-*-*-*', \
+               '-*-helvetica-bold-r-normal-*-*-180-100-*-*-*-*-*', \
+               ]
+       h2fontset = [ \
+               '-*-helvetica-medium-r-normal-*-*-140-100-*-*-*-*-*', \
+               '-*-helvetica-medium-o-normal-*-*-140-100-*-*-*-*-*', \
+               '-*-helvetica-bold-r-normal-*-*-140-100-*-*-*-*-*', \
+               ]
+       h3fontset = [ \
+               '-*-helvetica-medium-r-normal-*-*-120-100-*-*-*-*-*', \
+               '-*-helvetica-medium-o-normal-*-*-120-100-*-*-*-*-*', \
+               '-*-helvetica-bold-r-normal-*-*-120-100-*-*-*-*-*', \
+               ]
+       ddindent = 40
+
+
+class MacStylesheet(NullStylesheet):
+       stdfontset = [ \
+               ('Geneva', 'p', 10), \
+               ('Geneva', 'i', 10), \
+               ('Geneva', 'b', 10), \
+               ('Monaco', 'p', 10), \
+               ]
+       h1fontset = [ \
+               ('Geneva', 'p', 18), \
+               ('Geneva', 'i', 18), \
+               ('Geneva', 'b', 18), \
+               ('Monaco', 'p', 18), \
+               ]
+       h3fontset = [ \
+               ('Geneva', 'p', 14), \
+               ('Geneva', 'i', 14), \
+               ('Geneva', 'b', 14), \
+               ('Monaco', 'p', 14), \
+               ]
+       h3fontset = [ \
+               ('Geneva', 'p', 12), \
+               ('Geneva', 'i', 12), \
+               ('Geneva', 'b', 12), \
+               ('Monaco', 'p', 12), \
+               ]
+
+
+if os.name == 'mac':
+       StdwinStylesheet = MacStylesheet
+else:
+       StdwinStylesheet = X11Stylesheet
+
+
+class GLStylesheet(NullStylesheet):
+       stdfontset = [ \
+               'Helvetica 10', \
+               'Helvetica-Italic 10', \
+               'Helvetica-Bold 10', \
+               'Courier 10', \
+               ]
+       h1fontset = [ \
+               'Helvetica 18', \
+               'Helvetica-Italic 18', \
+               'Helvetica-Bold 18', \
+               'Courier 18', \
+               ]
+       h2fontset = [ \
+               'Helvetica 14', \
+               'Helvetica-Italic 14', \
+               'Helvetica-Bold 14', \
+               'Courier 14', \
+               ]
+       h3fontset = [ \
+               'Helvetica 12', \
+               'Helvetica-Italic 12', \
+               'Helvetica-Bold 12', \
+               'Courier 12', \
+               ]
+
+
+# Test program -- produces no output but times how long it takes
+# to send a document to a null formatter, exclusive of I/O
+
+def test():
+       import fmt
+       import time
+       import urllib
+       if sys.argv[1:]: file = sys.argv[1]
+       else: file = 'test.html'
+       data = urllib.urlopen(file).read()
+       t0 = time.time()
+       fmtr = fmt.WritingFormatter(sys.stdout, 79)
+       p = FormattingParser(fmtr, NullStylesheet)
+       p.feed(data)
+       p.close()
+       t1 = time.time()
+       print
+       print '*** Formatting time:', round(t1-t0, 3), 'seconds.'
+
+
+# Test program using stdwin
+
+def testStdwin():
+       import stdwin, fmt
+       from stdwinevents import *
+       if sys.argv[1:]: file = sys.argv[1]
+       else: file = 'test.html'
+       data = open(file, 'r').read()
+       window = stdwin.open('testStdwin')
+       b = None
+       while 1:
+               etype, ewin, edetail = stdwin.getevent()
+               if etype == WE_CLOSE:
+                       break
+               if etype == WE_SIZE:
+                       window.setdocsize(0, 0)
+                       window.setorigin(0, 0)
+                       window.change((0, 0), (10000, 30000)) # XXX
+               if etype == WE_DRAW:
+                       if not b:
+                               b = fmt.StdwinBackEnd(window, 1)
+                               f = fmt.BaseFormatter(b.d, b)
+                               p = FormattingParser(f, \
+                                                           MacStylesheet)
+                               p.feed(data)
+                               p.close()
+                               b.finish()
+                       else:
+                               b.redraw(edetail)
+       window.close()
+
+
+# Test program using GL
+
+def testGL():
+       import gl, GL, fmt
+       if sys.argv[1:]: file = sys.argv[1]
+       else: file = 'test.html'
+       data = open(file, 'r').read()
+       W, H = 600, 600
+       gl.foreground()
+       gl.prefsize(W, H)
+       wid = gl.winopen('testGL')
+       gl.ortho2(0, W, H, 0)
+       gl.color(GL.WHITE)
+       gl.clear()
+       gl.color(GL.BLACK)
+       b = fmt.GLBackEnd(wid)
+       f = fmt.BaseFormatter(b.d, b)
+       p = FormattingParser(f, GLStylesheet)
+       p.feed(data)
+       p.close()
+       b.finish()
+       #
+       import time
+       time.sleep(5)
+
+
+if __name__ == '__main__':
+       test()
diff --git a/Demo/tkinter/www/sgmllib.py b/Demo/tkinter/www/sgmllib.py
new file mode 100755 (executable)
index 0000000..af75e0d
--- /dev/null
@@ -0,0 +1,321 @@
+# A parser for SGML, using the derived class as static DTD.
+
+# XXX This only supports those SGML features used by HTML.
+
+# XXX There should be a way to distinguish between PCDATA (parsed
+# character data -- the normal case), RCDATA (replaceable character
+# data -- only char and entity references and end tags are special)
+# and CDATA (character data -- only end tags are special).
+
+
+import regex
+import string
+
+
+# Regular expressions used for parsing
+
+incomplete = regex.compile( \
+         '<!-?\|</[a-zA-Z][a-zA-Z0-9]*[ \t\n]*\|</?\|' + \
+         '&#[a-zA-Z0-9]*\|&[a-zA-Z][a-zA-Z0-9]*\|&')
+entityref = regex.compile('&[a-zA-Z][a-zA-Z0-9]*[;.]')
+charref = regex.compile('&#[a-zA-Z0-9]+;')
+starttagopen = regex.compile('<[a-zA-Z]')
+endtag = regex.compile('</[a-zA-Z][a-zA-Z0-9]*[ \t\n]*>')
+commentopen = regex.compile('<!--')
+
+
+# SGML parser base class -- find tags and call handler functions.
+# Usage: p = SGMLParser(); p.feed(data); ...; p.close().
+# The dtd is defined by deriving a class which defines methods
+# with special names to handle tags: start_foo and end_foo to handle
+# <foo> and </foo>, respectively, or do_foo to handle <foo> by itself.
+# (Tags are converted to lower case for this purpose.)  The data
+# between tags is passed to the parser by calling self.handle_data()
+# with some data as argument (the data may be split up in arbutrary
+# chunks).  Entity references are passed by calling
+# self.handle_entityref() with the entity reference as argument.
+
+class SGMLParser:
+
+       # Interface -- initialize and reset this instance
+       def __init__(self):
+               self.reset()
+
+       # Interface -- reset this instance.  Loses all unprocessed data
+       def reset(self):
+               self.rawdata = ''
+               self.stack = []
+               self.nomoretags = 0
+               self.literal = 0
+
+       # For derived classes only -- enter literal mode (CDATA) till EOF
+       def setnomoretags(self):
+               self.nomoretags = self.literal = 1
+
+       # For derived classes only -- enter literal mode (CDATA)
+       def setliteral(self, *args):
+               self.literal = 1
+
+       # Interface -- feed some data to the parser.  Call this as
+       # often as you want, with as little or as much text as you
+       # want (may include '\n').  (This just saves the text, all the
+       # processing is done by process() or close().)
+       def feed(self, data):
+               self.rawdata = self.rawdata + data
+               self.goahead(0)
+
+       # Interface -- handle the remaining data
+       def close(self):
+               self.goahead(1)
+
+       # Internal -- handle data as far as reasonable.  May leave state
+       # and data to be processed by a subsequent call.  If 'end' is
+       # true, force handling all data as if followed by EOF marker.
+       def goahead(self, end):
+               rawdata = self.rawdata
+               i = 0
+               n = len(rawdata)
+               while i < n:
+                       if self.nomoretags:
+                               self.handle_data(rawdata[i:n])
+                               i = n
+                               break
+                       j = incomplete.search(rawdata, i)
+                       if j < 0: j = n
+                       if i < j: self.handle_data(rawdata[i:j])
+                       i = j
+                       if i == n: break
+                       if rawdata[i] == '<':
+                               if starttagopen.match(rawdata, i) >= 0:
+                                       if self.literal:
+                                               self.handle_data(rawdata[i])
+                                               i = i+1
+                                               continue
+                                       k = self.parse_starttag(i)
+                                       if k < 0: break
+                                       i = i + k
+                                       continue
+                               k = endtag.match(rawdata, i)
+                               if k >= 0:
+                                       j = i+k
+                                       self.parse_endtag(rawdata[i:j])
+                                       i = j
+                                       self.literal = 0
+                                       continue
+                               if commentopen.match(rawdata, i) >= 0:
+                                       if self.literal:
+                                               self.handle_data(rawdata[i])
+                                               i = i+1
+                                               continue
+                                       k = self.parse_comment(i)
+                                       if k < 0: break
+                                       i = i+k
+                                       continue
+                       elif rawdata[i] == '&':
+                               k = charref.match(rawdata, i)
+                               if k >= 0:
+                                       j = i+k
+                                       self.handle_charref(rawdata[i+2:j-1])
+                                       i = j
+                                       continue
+                               k = entityref.match(rawdata, i)
+                               if k >= 0:
+                                       j = i+k
+                                       self.handle_entityref(rawdata[i+1:j-1])
+                                       i = j
+                                       continue
+                       else:
+                               raise RuntimeError, 'neither < nor & ??'
+                       # We get here only if incomplete matches but
+                       # nothing else
+                       k = incomplete.match(rawdata, i)
+                       if k < 0: raise RuntimeError, 'no incomplete match ??'
+                       j = i+k
+                       if j == n: break # Really incomplete
+                       self.handle_data(rawdata[i:j])
+                       i = j
+               # end while
+               if end and i < n:
+                       self.handle_data(rawdata[i:n])
+                       i = n
+               self.rawdata = rawdata[i:]
+               # XXX if end: check for empty stack
+
+       # Internal -- parse comment, return length or -1 if not ternimated
+       def parse_comment(self, i):
+               rawdata = self.rawdata
+               if rawdata[i:i+4] <> '<!--':
+                       raise RuntimeError, 'unexpected call to handle_comment'
+               try:
+                       j = string.index(rawdata, '--', i+4)
+               except string.index_error:
+                       return -1
+               self.handle_comment(rawdata[i+4: j])
+               j = j+2
+               n = len(rawdata)
+               while j < n and rawdata[j] in ' \t\n': j = j+1
+               if j == n: return -1 # Wait for final '>'
+               if rawdata[j] == '>':
+                       j = j+1
+               else:
+                       print '*** comment not terminated with >'
+                       print repr(rawdata[j-5:j]), '*!*', repr(rawdata[j:j+5])
+               return j-i
+
+       # Internal -- handle starttag, return length or -1 if not terminated
+       def parse_starttag(self, i):
+               rawdata = self.rawdata
+               try:
+                       j = string.index(rawdata, '>', i)
+               except string.index_error:
+                       return -1
+               # Now parse the data between i+1 and j into a tag and attrs
+               attrs = []
+               tagfind = regex.compile('[a-zA-Z][a-zA-Z0-9]*')
+               attrfind = regex.compile( \
+                 '[ \t\n]+\([a-zA-Z][a-zA-Z0-9]*\)' + \
+                 '\([ \t\n]*=[ \t\n]*' + \
+                    '\(\'[^\']*\';\|"[^"]*"\|[-a-zA-Z0-9./:+*%?!()_#]+\)\)?')
+               k = tagfind.match(rawdata, i+1)
+               if k < 0:
+                       raise RuntimeError, 'unexpected call to parse_starttag'
+               k = i+1+k
+               tag = string.lower(rawdata[i+1:k])
+               while k < j:
+                       l = attrfind.match(rawdata, k)
+                       if l < 0: break
+                       regs = attrfind.regs
+                       a1, b1 = regs[1]
+                       a2, b2 = regs[2]
+                       a3, b3 = regs[3]
+                       attrname = rawdata[a1:b1]
+                       if '=' in rawdata[k:k+l]:
+                               attrvalue = rawdata[a3:b3]
+                               if attrvalue[:1] == '\'' == attrvalue[-1:] or \
+                                  attrvalue[:1] == '"' == attrvalue[-1:]:
+                                       attrvalue = attrvalue[1:-1]
+                       else:
+                               attrvalue = ''
+                       attrs.append(string.lower(attrname), attrvalue)
+                       k = k + l
+               j = j+1
+               try:
+                       method = getattr(self, 'start_' + tag)
+               except AttributeError:
+                       try:
+                               method = getattr(self, 'do_' + tag)
+                       except AttributeError:
+                               self.unknown_starttag(tag, attrs)
+                               return j-i
+                       method(attrs)
+                       return j-i
+               self.stack.append(tag)
+               method(attrs)
+               return j-i
+
+       # Internal -- parse endtag
+       def parse_endtag(self, data):
+               if data[:2] <> '</' or data[-1:] <> '>':
+                       raise RuntimeError, 'unexpected call to parse_endtag'
+               tag = string.lower(string.strip(data[2:-1]))
+               try:
+                       method = getattr(self, 'end_' + tag)
+               except AttributeError:
+                       self.unknown_endtag(tag)
+                       return
+               if self.stack and self.stack[-1] == tag:
+                       del self.stack[-1]
+               else:
+                       print '*** Unbalanced </' + tag + '>'
+                       print '*** Stack:', self.stack
+                       found = None
+                       for i in range(len(self.stack)):
+                               if self.stack[i] == tag: found = i
+                       if found <> None:
+                               del self.stack[found:]
+               method()
+
+       # Example -- handle character reference, no need to override
+       def handle_charref(self, name):
+               try:
+                       n = string.atoi(name)
+               except string.atoi_error:
+                       self.unknown_charref(name)
+                       return
+               if not 0 <= n <= 255:
+                       self.unknown_charref(name)
+                       return
+               self.handle_data(chr(n))
+
+       # Definition of entities -- derived classes may override
+       entitydefs = \
+               {'lt': '<', 'gt': '>', 'amp': '&', 'quot': '"', 'apos': '\''}
+
+       # Example -- handle entity reference, no need to override
+       def handle_entityref(self, name):
+               table = self.__class__.entitydefs
+               name = string.lower(name)
+               if table.has_key(name):
+                       self.handle_data(table[name])
+               else:
+                       self.unknown_entityref(name)
+                       return
+
+       # Example -- handle data, should be overridden
+       def handle_data(self, data):
+               pass
+
+       # Example -- handle comment, could be overridden
+       def handle_comment(self, data):
+               pass
+
+       # To be overridden -- handlers for unknown objects
+       def unknown_starttag(self, tag, attrs): pass
+       def unknown_endtag(self, tag): pass
+       def unknown_charref(self, ref): pass
+       def unknown_entityref(self, ref): pass
+
+
+class TestSGML(SGMLParser):
+
+       def handle_data(self, data):
+               r = repr(data)
+               if len(r) > 72:
+                       r = r[:35] + '...' + r[-35:]
+               print 'data:', r
+
+       def handle_comment(self, data):
+               r = repr(data)
+               if len(r) > 68:
+                       r = r[:32] + '...' + r[-32:]
+               print 'comment:', r
+
+       def unknown_starttag(self, tag, attrs):
+               print 'start tag: <' + tag,
+               for name, value in attrs:
+                       print name + '=' + '"' + value + '"',
+               print '>'
+
+       def unknown_endtag(self, tag):
+               print 'end tag: </' + tag + '>'
+
+       def unknown_entityref(self, ref):
+               print '*** unknown entity ref: &' + ref + ';'
+
+       def unknown_charref(self, ref):
+               print '*** unknown char ref: &#' + ref + ';'
+
+
+def test():
+       file = 'test.html'
+       f = open(file, 'r')
+       x = TestSGML()
+       while 1:
+               line = f.readline()
+               if not line:
+                       x.close()
+                       break
+               x.feed(line)
+
+
+#test()
diff --git a/Demo/tkinter/www/tkfmt.py b/Demo/tkinter/www/tkfmt.py
new file mode 100755 (executable)
index 0000000..adbb002
--- /dev/null
@@ -0,0 +1,63 @@
+# Tk backend -- unfinished
+
+debug = 0
+
+from fmt import *
+
+class TkFormatter:
+
+       def __init__(self, text):
+               self.text = text        # The text widget to draw in
+               self.nospace = 1
+               self.blanklines = 0
+               self.font = ''
+
+       # Methods called by htmllib.FormattingParser:
+
+       def setfont(self, font):
+               if 1 or debug: print "setfont(%s)" % `font`
+               self.font = font
+
+       def resetfont(self):
+               if debug: print "resetfont()"
+               self.font = ''
+
+       def flush(self):
+               if debug: print "flush()"
+               self.needvspace(1)
+
+       def setleftindent(self, n):
+               if debug: print "setleftindent(%d)" % n
+
+       def needvspace(self, n):
+               if debug: print "needvspace(%d)" % n
+               self.blanklines = max(n, self.blanklines)
+               self.nospace = 1
+
+       def addword(self, word, nspaces):
+               if debug: print "addword(%s, %d)" % (`word`, nspaces)
+               if self.nospace and not word:
+                       return
+               if self.blanklines > 0:
+                       word = '\n'*self.blanklines + word
+               self.blanklines = 0
+               self.nospace = 0
+               here = self.text.index('end')
+               self.text.insert('end', word + nspaces*' ')
+               if not self.font:
+                       self.tag_remo
+
+       def setjust(self, c):
+               if debug: print "setjust(%s)" % `c`
+
+       def bgn_anchor(self):
+               if debug: print "bgn_anchor()"
+
+       def end_anchor(self):
+               if debug: print "end_anchor()"
+
+       def hrule(self):
+               if debug: print "hrule()"
+               self.flush()
+               self.addword('_'*60, 0)
+               self.flush()
diff --git a/Demo/tkinter/www/www1.py b/Demo/tkinter/www/www1.py
new file mode 100755 (executable)
index 0000000..dc30e21
--- /dev/null
@@ -0,0 +1,19 @@
+#! /usr/local/bin/python
+
+# www1.py -- print the contents of a URL on stdout
+
+import sys
+import urllib
+
+def main():
+       if len(sys.argv) != 2 or sys.argv[1][:1] == '-':
+               print "Usage:", sys.argv[0], "url"
+               sys.exit(2)
+       url = sys.argv[1]
+       fp = urllib.urlopen(url)
+       while 1:
+               line = fp.readline()
+               if not line: break
+               print line,
+
+main()
diff --git a/Demo/tkinter/www/www10.py b/Demo/tkinter/www/www10.py
new file mode 100755 (executable)
index 0000000..def5196
--- /dev/null
@@ -0,0 +1,101 @@
+#! /usr/local/bin/python
+
+# www10.py -- display the contents of a URL in a Text widget
+# - set window title
+# - make window resizable
+# - update display while reading
+# - vertical scroll bar
+# - rewritten as class
+# - editable url entry and reload button
+
+import sys
+import urllib
+from Tkinter import *
+
+def main():
+       if len(sys.argv) != 2 or sys.argv[1][:1] == '-':
+               print "Usage:", sys.argv[0], "url"
+               sys.exit(2)
+       url = sys.argv[1]
+       viewer = Viewer()
+       viewer.load(url)
+       viewer.go()
+
+class Viewer:
+
+       def __init__(self):
+               # Create root window
+               self.root = Tk()
+               self.root.minsize(1, 1)
+
+               # Create topframe for the entry and button
+               self.topframe = Frame(self.root)
+               self.topframe.pack({'fill': 'x', 'side': 'top'})
+
+               # Create a label in front of the entry
+               self.urllabel = Label(self.topframe, {'text': 'URL:'})
+               self.urllabel.pack({'side': 'left'})
+
+               # Create the entry containing the URL
+               self.entry = Entry(self.topframe, {'relief': 'sunken'})
+               self.entry.pack({'side': 'left', 'fill': 'x', 'expand': 1})
+               self.entry.bind('<Return>', self.loadit)
+
+               # Create the button
+               self.reload = Button(self.topframe,
+                                    {'text': 'Reload',
+                                     'command': self.reload})
+               self.reload.pack({'side': 'right'})
+
+               # Create botframe for the text and scrollbar
+               self.botframe = Frame(self.root)
+               self.botframe.pack({'fill': 'both', 'expand': 1})
+
+               # The Scrollbar *must* be created first
+               self.vbar = Scrollbar(self.botframe)
+               self.vbar.pack({'fill': 'y', 'side': 'right'})
+               self.text = Text(self.botframe)
+               self.text.pack({'expand': 1, 'fill': 'both', 'side': 'left'})
+
+               # Link Text widget and Scrollbar
+               self.text['yscrollcommand'] = (self.vbar, 'set')
+               self.vbar['command'] = (self.text, 'yview')
+
+               self.url = None
+
+       def load(self, url):
+               # Load a new URL into the window
+               fp = urllib.urlopen(url)
+
+               self.url = url
+
+               self.root.title(url)
+
+               self.entry.delete('0', 'end')
+               self.entry.insert('end', url)
+
+               self.text.delete('1.0', 'end')
+
+               while 1:
+                       line = fp.readline()
+                       if not line: break
+                       if line[-2:] == '\r\n': line = line[:-2] + '\n'
+                       self.text.insert('end', line)
+                       self.root.update_idletasks()
+
+               fp.close()
+
+       def go(self):
+               # Start Tk main loop
+               self.root.mainloop()
+
+       def reload(self, *args):
+               # Callback for Reload button
+               if self.url:
+                       self.load(self.url)
+
+       def loadit(self, *args):
+               # Callback for <Return> event in entry
+               self.load(self.entry.get())
+
+main()
diff --git a/Demo/tkinter/www/www11.py b/Demo/tkinter/www/www11.py
new file mode 100755 (executable)
index 0000000..59b71c0
--- /dev/null
@@ -0,0 +1,137 @@
+#! /usr/local/bin/python
+
+# www11.py -- display the contents of a URL in a Text widget
+# - set window title
+# - make window resizable
+# - update display while reading
+# - vertical scroll bar
+# - rewritten as class
+# - editable url entry and reload button
+# - error dialog
+
+import sys
+import urllib
+from Tkinter import *
+import Dialog
+
+def main():
+       if len(sys.argv) != 2 or sys.argv[1][:1] == '-':
+               print "Usage:", sys.argv[0], "url"
+               sys.exit(2)
+       url = sys.argv[1]
+       viewer = Viewer()
+       viewer.load(url)
+       viewer.go()
+
+class Viewer:
+
+       def __init__(self):
+               # Create root window
+               self.root = Tk()
+               self.root.minsize(1, 1)
+
+               # Create topframe for the entry and button
+               self.topframe = Frame(self.root)
+               self.topframe.pack({'fill': 'x'})
+
+               # Create a label in front of the entry
+               self.urllabel = Label(self.topframe, {'text': 'URL:'})
+               self.urllabel.pack({'side': 'left'})
+
+               # Create the entry containing the URL
+               self.entry = Entry(self.topframe,
+                                  {'relief': 'sunken', 'border': 2})
+               self.entry.pack({'side': 'left', 'fill': 'x', 'expand': 1})
+               self.entry.bind('<Return>', self.loadit)
+
+               # Create the button
+               self.reload = Button(self.topframe,
+                                    {'text': 'Reload',
+                                     'command': self.reload})
+               self.reload.pack({'side': 'right'})
+
+               # Create botframe for the text and scrollbar
+               self.botframe = Frame(self.root)
+               self.botframe.pack({'fill': 'both', 'expand': 1})
+
+               # The Scrollbar *must* be created first
+               self.vbar = Scrollbar(self.botframe)
+               self.vbar.pack({'fill': 'y', 'side': 'right'})
+               self.text = Text(self.botframe)
+               self.text.pack({'expand': 1, 'fill': 'both', 'side': 'left'})
+
+               # Link Text widget and Scrollbar
+               self.text['yscrollcommand'] = (self.vbar, 'set')
+               self.vbar['command'] = (self.text, 'yview')
+
+               self.url = None
+
+       def load(self, url):
+               # Load a new URL into the window
+               fp, url = self.urlopen(url)
+               if not fp:
+                       return
+
+               self.url = url
+
+               self.root.title(url)
+
+               self.entry.delete('0', 'end')
+               self.entry.insert('end', url)
+
+               self.text.delete('0.0', 'end')
+
+               while 1:
+                       line = fp.readline()
+                       if not line: break
+                       if line[-2:] == '\r\n': line = line[:-2] + '\n'
+                       self.text.insert('end', line)
+                       self.root.update_idletasks()
+
+               fp.close()
+
+       def urlopen(self, url):
+               # Open a URL --
+               # return (fp, url) if successful
+               # display dialog and return (None, url) for errors
+               try:
+                       fp = urllib.urlopen(url)
+               except IOError, msg:
+                       import types
+                       if type(msg) == types.TupleType and len(msg) == 4:
+                               if msg[1] == 302:
+                                       m = msg[3]
+                                       if m.has_key('location'):
+                                               url = m['location']
+                                               return self.urlopen(url)
+                                       elif m.has_key('uri'):
+                                               url = m['uri']
+                                               return self.urlopen(url)
+                       self.errordialog(IOError, msg)
+                       fp = None
+               return fp, url
+
+       def errordialog(self, exc, msg):
+               # Display an error dialog -- return when the user clicks OK
+               Dialog.Dialog(self.root, {
+                       'text': str(msg),
+                       'title': exc,
+                       'bitmap': 'error',
+                       'default': 0,
+                       'strings': ('OK',),
+                       })
+
+       def go(self):
+               # Start Tk main loop
+               self.root.mainloop()
+
+       def reload(self, *args):
+               # Callback for Reload button
+               if self.url:
+                       self.load(self.url)
+
+       def loadit(self, *args):
+               # Callback for <Return> event in entry
+               self.load(self.entry.get())
+
+main()
diff --git a/Demo/tkinter/www/www12.py b/Demo/tkinter/www/www12.py
new file mode 100755 (executable)
index 0000000..2e870c4
--- /dev/null
@@ -0,0 +1,210 @@
+#! /usr/local/bin/python
+
+# www12.py -- display the contents of a URL in a Text widget
+# - set window title
+# - make window resizable
+# - update display while reading
+# - vertical scroll bar
+# - rewritten as class
+# - editable url entry and reload button
+# - error dialog
+# - menu bar; added 'master' option to constructor
+
+import sys
+import urllib
+from Tkinter import *
+import Dialog
+
+def main():
+       if len(sys.argv) != 2 or sys.argv[1][:1] == '-':
+               print "Usage:", sys.argv[0], "url"
+               sys.exit(2)
+       url = sys.argv[1]
+       tk = Tk()
+       tk.withdraw()
+       viewer = Viewer(tk)
+       viewer.load(url)
+       viewer.go()
+
+class Viewer:
+
+       def __init__(self, master = None):
+               # Create root window
+               if master is None:
+                       self.root = self.master = Tk()
+               else:
+                       self.master = master
+                       self.root = Toplevel(self.master)
+               self.root.minsize(1, 1)
+
+               # Create menu bar
+               self.mbar = Frame(self.root,
+                                 {'relief': 'raised',
+                                  'border': 2})
+               self.mbar.pack({'fill': 'x'})
+
+               # Create File menu
+               self.filebutton = Menubutton(self.mbar, {'text': 'File'})
+               self.filebutton.pack({'side': 'left'})
+
+               self.filemenu = Menu(self.filebutton)
+               self.filebutton['menu'] = self.filemenu
+
+               # Create Edit menu
+               self.editbutton = Menubutton(self.mbar, {'text': 'Edit'})
+               self.editbutton.pack({'side': 'left'})
+
+               self.editmenu = Menu(self.editbutton)
+               self.editbutton['menu'] = self.editmenu
+
+               # Magic so you can swipe from one button to the next
+               self.mbar.tk_menuBar(self.filebutton, self.editbutton)
+
+               # Populate File menu
+               self.filemenu.add('command', {'label': 'New',
+                                             'command': self.new_command})
+               self.filemenu.add('command', {'label': 'Open...',
+                                             'command': self.open_command})
+               self.filemenu.add('command', {'label': 'Clone',
+                                             'command': self.clone_command})
+               self.filemenu.add('separator')
+               self.filemenu.add('command', {'label': 'Close',
+                                             'command': self.close_command})
+               self.filemenu.add('command', {'label': 'Quit',
+                                             'command': self.quit_command})
+
+               # Populate Edit menu
+               pass
+
+               # Create topframe for the entry and button
+               self.topframe = Frame(self.root)
+               self.topframe.pack({'fill': 'x'})
+
+               # Create a label in front of the entry
+               self.urllabel = Label(self.topframe, {'text': 'URL:'})
+               self.urllabel.pack({'side': 'left'})
+
+               # Create the entry containing the URL
+               self.entry = Entry(self.topframe,
+                                  {'relief': 'sunken', 'border': 2})
+               self.entry.pack({'side': 'left', 'fill': 'x', 'expand': 1})
+               self.entry.bind('<Return>', self.loadit)
+
+               # Create the button
+               self.reload = Button(self.topframe,
+                                    {'text': 'Reload',
+                                     'command': self.reload})
+               self.reload.pack({'side': 'right'})
+
+               # Create botframe for the text and scrollbar
+               self.botframe = Frame(self.root)
+               self.botframe.pack({'fill': 'both', 'expand': 1})
+
+               # The Scrollbar *must* be created first
+               self.vbar = Scrollbar(self.botframe)
+               self.vbar.pack({'fill': 'y', 'side': 'right'})
+               self.text = Text(self.botframe)
+               self.text.pack({'expand': 1, 'fill': 'both', 'side': 'left'})
+
+               # Link Text widget and Scrollbar
+               self.text['yscrollcommand'] = (self.vbar, 'set')
+               self.vbar['command'] = (self.text, 'yview')
+
+               self.url = None
+
+       def load(self, url):
+               # Load a new URL into the window
+               fp, url = self.urlopen(url)
+               if not fp:
+                       return
+
+               self.url = url
+
+               self.root.title(url)
+
+               self.entry.delete('0', 'end')
+               self.entry.insert('end', url)
+
+               self.text.delete('0.0', 'end')
+
+               while 1:
+                       line = fp.readline()
+                       if not line: break
+                       if line[-2:] == '\r\n': line = line[:-2] + '\n'
+                       self.text.insert('end', line)
+                       self.root.update_idletasks()
+
+               fp.close()
+
+       def urlopen(self, url):
+               # Open a URL --
+               # return (fp, url) if successful
+               # display dialog and return (None, url) for errors
+               try:
+                       fp = urllib.urlopen(url)
+               except IOError, msg:
+                       import types
+                       if type(msg) == types.TupleType and len(msg) == 4:
+                               if msg[1] == 302:
+                                       m = msg[3]
+                                       if m.has_key('location'):
+                                               url = m['location']
+                                               return self.urlopen(url)
+                                       elif m.has_key('uri'):
+                                               url = m['uri']
+                                               return self.urlopen(url)
+                       self.errordialog(IOError, msg)
+                       fp = None
+               return fp, url
+
+       def errordialog(self, exc, msg):
+               # Display an error dialog -- return when the user clicks OK
+               Dialog.Dialog(self.root, {
+                       'text': str(msg),
+                       'title': exc,
+                       'bitmap': 'error',
+                       'default': 0,
+                       'strings': ('OK',),
+                       })
+
+       def go(self):
+               # Start Tk main loop
+               self.root.mainloop()
+
+       def reload(self, *args):
+               # Callback for Reload button
+               if self.url:
+                       self.load(self.url)
+
+       def loadit(self, *args):
+               # Callback for <Return> event in entry
+               self.load(self.entry.get())
+
+       def new_command(self):
+               # File/New...
+               Viewer(self.master)
+
+       def clone_command(self):
+               # File/Clone
+               v = Viewer(self.master)
+               v.load(self.url)
+
+       def open_command(self):
+               # File/Open...
+               print "File/Open...: Not implemented"
+
+       def close_command(self):
+               # File/Close
+               self.destroy()
+
+       def quit_command(self):
+               # File/Quit
+               self.root.quit()
+
+       def destroy(self):
+               # Destroy this window
+               self.root.destroy()
+               if self.master is not self.root and not self.master.children:
+                       self.master.quit()
+
+main()
diff --git a/Demo/tkinter/www/www13.py b/Demo/tkinter/www/www13.py
new file mode 100755 (executable)
index 0000000..af9b176
--- /dev/null
@@ -0,0 +1,218 @@
+#! /usr/local/bin/python
+
+# www13.py -- display the contents of a URL in a Text widget
+# - set window title
+# - make window resizable
+# - update display while reading
+# - vertical scroll bar
+# - rewritten as class
+# - editable url entry and reload button
+# - error dialog
+# - menu bar; added 'master' option to constructor
+# - Added HTML parser
+
+import sys
+import urllib
+from Tkinter import *
+import Dialog
+import tkfmt
+import htmllib
+
+def main():
+       if len(sys.argv) != 2 or sys.argv[1][:1] == '-':
+               print "Usage:", sys.argv[0], "url"
+               sys.exit(2)
+       url = sys.argv[1]
+       tk = Tk()
+       tk.withdraw()
+       viewer = Viewer(tk)
+       viewer.load(url)
+       viewer.go()
+
+class Viewer:
+
+       def __init__(self, master = None):
+               # Create root window
+               if master is None:
+                       self.root = self.master = Tk()
+               else:
+                       self.master = master
+                       self.root = Toplevel(self.master)
+               self.root.minsize(1, 1)
+
+               # Create menu bar
+               self.mbar = Frame(self.root,
+                                 {'relief': 'raised',
+                                  'border': 2})
+               self.mbar.pack({'fill': 'x'})
+
+               # Create File menu
+               self.filebutton = Menubutton(self.mbar, {'text': 'File'})
+               self.filebutton.pack({'side': 'left'})
+
+               self.filemenu = Menu(self.filebutton)
+               self.filebutton['menu'] = self.filemenu
+
+               # Create Edit menu
+               self.editbutton = Menubutton(self.mbar, {'text': 'Edit'})
+               self.editbutton.pack({'side': 'left'})
+
+               self.editmenu = Menu(self.editbutton)
+               self.editbutton['menu'] = self.editmenu
+
+               # Magic so you can swipe from one button to the next
+               self.mbar.tk_menuBar(self.filebutton, self.editbutton)
+
+               # Populate File menu
+               self.filemenu.add('command', {'label': 'New',
+                                             'command': self.new_command})
+               self.filemenu.add('command', {'label': 'Open...',
+                                             'command': self.open_command})
+               self.filemenu.add('command', {'label': 'Clone',
+                                             'command': self.clone_command})
+               self.filemenu.add('separator')
+               self.filemenu.add('command', {'label': 'Close',
+                                             'command': self.close_command})
+               self.filemenu.add('command', {'label': 'Quit',
+                                             'command': self.quit_command})
+
+               # Populate Edit menu
+               pass
+
+               # Create topframe for the entry and button
+               self.topframe = Frame(self.root)
+               self.topframe.pack({'fill': 'x'})
+
+               # Create a label in front of the entry
+               self.urllabel = Label(self.topframe, {'text': 'URL:'})
+               self.urllabel.pack({'side': 'left'})
+
+               # Create the entry containing the URL
+               self.entry = Entry(self.topframe,
+                                  {'relief': 'sunken', 'border': 2})
+               self.entry.pack({'side': 'left', 'fill': 'x', 'expand': 1})
+               self.entry.bind('<Return>', self.loadit)
+
+               # Create the button
+               self.reload = Button(self.topframe,
+                                    {'text': 'Reload',
+                                     'command': self.reload})
+               self.reload.pack({'side': 'right'})
+
+               # Create botframe for the text and scrollbar
+               self.botframe = Frame(self.root)
+               self.botframe.pack({'fill': 'both', 'expand': 1})
+
+               # The Scrollbar *must* be created first
+               self.vbar = Scrollbar(self.botframe)
+               self.vbar.pack({'fill': 'y', 'side': 'right'})
+               self.text = Text(self.botframe)
+               self.text.pack({'expand': 1, 'fill': 'both', 'side': 'left'})
+
+               # Link Text widget and Scrollbar
+               self.text['yscrollcommand'] = (self.vbar, 'set')
+               self.vbar['command'] = (self.text, 'yview')
+
+               self.url = None
+
+       def load(self, url):
+               # Load a new URL into the window
+               fp, url = self.urlopen(url)
+               if not fp:
+                       return
+
+               self.url = url
+
+               self.root.title(url)
+
+               self.entry.delete('0', 'end')
+               self.entry.insert('end', url)
+
+               self.text.delete('0.0', 'end')
+
+               f = tkfmt.TkFormatter(self.text)
+               p = htmllib.FormattingParser(f, htmllib.X11Stylesheet)
+
+               while 1:
+                       line = fp.readline()
+                       if not line: break
+                       if line[-2:] == '\r\n': line = line[:-2] + '\n'
+                       p.feed(line)
+                       self.root.update_idletasks()
+
+               p.close()
+
+               fp.close()
+
+       def urlopen(self, url):
+               # Open a URL --
+               # return (fp, url) if successful
+               # display dialog and return (None, url) for errors
+               try:
+                       fp = urllib.urlopen(url)
+               except IOError, msg:
+                       import types
+                       if type(msg) == types.TupleType and len(msg) == 4:
+                               if msg[1] == 302:
+                                       m = msg[3]
+                                       if m.has_key('location'):
+                                               url = m['location']
+                                               return self.urlopen(url)
+                                       elif m.has_key('uri'):
+                                               url = m['uri']
+                                               return self.urlopen(url)
+                       self.errordialog(IOError, msg)
+                       fp = None
+               return fp, url
+
+       def errordialog(self, exc, msg):
+               # Display an error dialog -- return when the user clicks OK
+               Dialog.Dialog(self.root, {
+                       'text': str(msg),
+                       'title': exc,
+                       'bitmap': 'error',
+                       'default': 0,
+                       'strings': ('OK',),
+                       })
+
+       def go(self):
+               # Start Tk main loop
+               self.root.mainloop()
+
+       def reload(self, *args):
+               # Callback for Reload button
+               if self.url:
+                       self.load(self.url)
+
+       def loadit(self, *args):
+               # Callback for <Return> event in entry
+               self.load(self.entry.get())
+
+       def new_command(self):
+               # File/New...
+               Viewer(self.master)
+
+       def clone_command(self):
+               # File/Clone
+               v = Viewer(self.master)
+               v.load(self.url)
+
+       def open_command(self):
+               # File/Open...
+               print "File/Open...: Not implemented"
+
+       def close_command(self):
+               # File/Close
+               self.destroy()
+
+       def quit_command(self):
+               # File/Quit
+               self.root.quit()
+
+       def destroy(self):
+               # Destroy this window
+               self.root.destroy()
+               if self.master is not self.root and not self.master.children:
+                       self.master.quit()
+
+main()
diff --git a/Demo/tkinter/www/www2.py b/Demo/tkinter/www/www2.py
new file mode 100755 (executable)
index 0000000..d14306a
--- /dev/null
@@ -0,0 +1,35 @@
+#! /usr/local/bin/python
+
+# www2.py -- print the contents of a URL on stdout
+# - error checking
+
+import sys
+import urllib
+import types
+
+def main():
+       if len(sys.argv) != 2 or sys.argv[1][:1] == '-':
+               print "Usage:", sys.argv[0], "url"
+               sys.exit(2)
+       url = sys.argv[1]
+       fp = my_urlopen(url)
+       while 1:
+               line = fp.readline()
+               if not line: break
+               sys.stdout.write(line)
+
+def my_urlopen(url):
+       try:
+               fp = urllib.urlopen(url)
+               return fp
+       except IOError, msg:
+               if type(msg) == types.TupleType and len(msg) == 4:
+                       print msg[:3]
+                       m = msg[3]
+                       for line in m.headers:
+                               sys.stdout.write(line)
+               else:
+                       print msg
+               sys.exit(1)
+
+main()
diff --git a/Demo/tkinter/www/www3.py b/Demo/tkinter/www/www3.py
new file mode 100755 (executable)
index 0000000..eb8b07f
--- /dev/null
@@ -0,0 +1,46 @@
+#! /usr/local/bin/python
+
+# www3.py -- print the contents of a URL on stdout
+# - error checking
+# - Error 302 handling
+
+import sys
+import urllib
+import types
+
+def main():
+       if len(sys.argv) != 2 or sys.argv[1][:1] == '-':
+               print "Usage:", sys.argv[0], "url"
+               sys.exit(2)
+       url = sys.argv[1]
+       fp = my_urlopen(url)
+       while 1:
+               line = fp.readline()
+               if not line: break
+               sys.stdout.write(line)
+
+def my_urlopen(url):
+       try:
+               fp = urllib.urlopen(url)
+               return fp
+       except IOError, msg:
+               if type(msg) == types.TupleType and len(msg) == 4:
+                       m = msg[3]
+                       if msg[1] == 302:
+                               if m.has_key('location'):
+                                       url = m['location']
+                                       print 'Location:', url
+                                       return my_urlopen(url)
+                               elif m.has_key('uri'):
+                                       url = m['uri']
+                                       print 'URI:', url
+                                       return my_urlopen(url)
+                               print '(Error 302 w/o Location/URI header???)'
+                       print msg[:3]
+                       for line in m.headers:
+                               sys.stdout.write(line)
+               else:
+                       print msg
+               sys.exit(1)
+
+main()
diff --git a/Demo/tkinter/www/www4.py b/Demo/tkinter/www/www4.py
new file mode 100755 (executable)
index 0000000..4351004
--- /dev/null
@@ -0,0 +1,26 @@
+#! /usr/local/bin/python
+
+# www4.py -- display the contents of a URL in a Text widget
+
+import sys
+import urllib
+from Tkinter import *
+
+def main():
+       if len(sys.argv) != 2 or sys.argv[1][:1] == '-':
+               print "Usage:", sys.argv[0], "url"
+               sys.exit(2)
+       url = sys.argv[1]
+       fp = urllib.urlopen(url)
+
+       text = Text()                   # Create text widget
+       text.pack()                     # Realize it
+
+       while 1:
+               line = fp.readline()
+               if not line: break
+               text.insert('end', line)        # Append line to text widget
+
+       text.mainloop()                 # Start Tk main loop
+
+main()
diff --git a/Demo/tkinter/www/www5.py b/Demo/tkinter/www/www5.py
new file mode 100755 (executable)
index 0000000..0ea451f
--- /dev/null
@@ -0,0 +1,29 @@
+#! /usr/local/bin/python
+
+# www5.py -- display the contents of a URL in a Text widget
+# - set window title
+
+import sys
+import urllib
+from Tkinter import *
+
+def main():
+       if len(sys.argv) != 2 or sys.argv[1][:1] == '-':
+               print "Usage:", sys.argv[0], "url"
+               sys.exit(2)
+       url = sys.argv[1]
+       fp = urllib.urlopen(url)
+
+       root = Tk()
+       root.title(url)                 # Set window manager title
+       text = Text(root)
+       text.pack()
+
+       while 1:
+               line = fp.readline()
+               if not line: break
+               text.insert('end', line)
+
+       text.mainloop()
+
+main()
diff --git a/Demo/tkinter/www/www6.py b/Demo/tkinter/www/www6.py
new file mode 100755 (executable)
index 0000000..a9b0698
--- /dev/null
@@ -0,0 +1,31 @@
+#! /usr/local/bin/python
+
+# www6.py -- display the contents of a URL in a Text widget
+# - set window title
+# - make window resizable
+
+import sys
+import urllib
+from Tkinter import *
+
+def main():
+       if len(sys.argv) != 2 or sys.argv[1][:1] == '-':
+               print "Usage:", sys.argv[0], "url"
+               sys.exit(2)
+       url = sys.argv[1]
+       fp = urllib.urlopen(url)
+
+       root = Tk()
+       root.title(url)
+       root.minsize(1, 1)              # Set minimum size
+       text = Text(root)
+       text.pack({'expand': 1, 'fill': 'both'}) # Expand into available space
+
+       while 1:
+               line = fp.readline()
+               if not line: break
+               text.insert('end', line)
+
+       root.mainloop()                 # Start Tk main loop (for root!)
+
+main()
diff --git a/Demo/tkinter/www/www7.py b/Demo/tkinter/www/www7.py
new file mode 100755 (executable)
index 0000000..cb4313d
--- /dev/null
@@ -0,0 +1,33 @@
+#! /usr/local/bin/python
+
+# www7.py -- display the contents of a URL in a Text widget
+# - set window title
+# - make window resizable
+# - update display while reading
+
+import sys
+import urllib
+from Tkinter import *
+
+def main():
+       if len(sys.argv) != 2 or sys.argv[1][:1] == '-':
+               print "Usage:", sys.argv[0], "url"
+               sys.exit(2)
+       url = sys.argv[1]
+       fp = urllib.urlopen(url)
+
+       root = Tk()
+       root.title(url)
+       root.minsize(1, 1)
+       text = Text(root)
+       text.pack({'expand': 1, 'fill': 'both'})
+
+       while 1:
+               line = fp.readline()
+               if not line: break
+               text.insert('end', line)
+               root.update_idletasks()         # Update display
+
+       root.mainloop()
+
+main()
diff --git a/Demo/tkinter/www/www8.py b/Demo/tkinter/www/www8.py
new file mode 100755 (executable)
index 0000000..868a7ed
--- /dev/null
@@ -0,0 +1,43 @@
+#! /usr/local/bin/python
+
+# www8.py -- display the contents of a URL in a Text widget
+# - set window title
+# - make window resizable
+# - update display while reading
+# - vertical scroll bar
+
+import sys
+import urllib
+from Tkinter import *
+
+def main():
+       if len(sys.argv) != 2 or sys.argv[1][:1] == '-':
+               print "Usage:", sys.argv[0], "url"
+               sys.exit(2)
+       url = sys.argv[1]
+       fp = urllib.urlopen(url)
+
+       # Create root window
+       root = Tk()
+       root.title(url)
+       root.minsize(1, 1)
+
+       # The Scrollbar *must* be created first -- this is magic for me :-(
+       vbar = Scrollbar(root)
+       vbar.pack({'fill': 'y', 'side': 'right'})
+       text = Text(root, {'yscrollcommand': (vbar, 'set')})
+       text.pack({'expand': 1, 'fill': 'both', 'side': 'left'})
+
+       # Link Text widget and Scrollbar -- this is magic for you :-)
+       ##text['yscrollcommand'] = (vbar, 'set')
+       vbar['command'] = (text, 'yview')
+
+       while 1:
+               line = fp.readline()
+               if not line: break
+               text.insert('end', line)
+               root.update_idletasks()
+
+       root.mainloop()
+
+main()
diff --git a/Demo/tkinter/www/www9.py b/Demo/tkinter/www/www9.py
new file mode 100755 (executable)
index 0000000..60b46ed
--- /dev/null
@@ -0,0 +1,60 @@
+#! /usr/local/bin/python
+
+# www9.py -- display the contents of a URL in a Text widget
+# - set window title
+# - make window resizable
+# - update display while reading
+# - vertical scroll bar
+# - rewritten as class
+
+import sys
+import urllib
+from Tkinter import *
+
+def main():
+       if len(sys.argv) != 2 or sys.argv[1][:1] == '-':
+               print "Usage:", sys.argv[0], "url"
+               sys.exit(2)
+       url = sys.argv[1]
+       viewer = Viewer()
+       viewer.load(url)
+       viewer.go()
+
+class Viewer:
+
+       def __init__(self):
+               # Create root window
+               self.root = Tk()
+               self.root.minsize(1, 1)
+
+               # The Scrollbar *must* be created first
+               self.vbar = Scrollbar(self.root)
+               self.vbar.pack({'fill': 'y', 'side': 'right'})
+               self.text = Text(self.root)
+               self.text.pack({'expand': 1, 'fill': 'both', 'side': 'left'})
+
+               # Link Text widget and Scrollbar
+               self.text['yscrollcommand'] = (self.vbar, 'set')
+               self.vbar['command'] = (self.text, 'yview')
+
+       def load(self, url):
+               # Load a new URL into the window
+               fp = urllib.urlopen(url)
+
+               self.root.title(url)
+
+               self.text.delete('0.0', 'end')
+
+               while 1:
+                       line = fp.readline()
+                       if not line: break
+                       self.text.insert('end', line)
+                       self.root.update_idletasks()
+
+               fp.close()
+
+       def go(self):
+               # Start Tk main loop
+               self.root.mainloop()
+
+main()