gcc/m2/gm2-libs/PushBackInput.def

   1 (* PushBackInput.def provides a method for pushing back and consuming input.
   2
   3 Copyright (C) 2001-2024 Free Software Foundation, Inc.
   4 Contributed by Gaius Mulley <gaius.mulley@southwales.ac.uk>.
   5
   6 This file is part of GNU Modula-2.
   7
   8 GNU Modula-2 is free software; you can redistribute it and/or modify
   9 it under the terms of the GNU General Public License as published by
  10 the Free Software Foundation; either version 3, or (at your option)
  11 any later version.
  12
  13 GNU Modula-2 is distributed in the hope that it will be useful, but
  14 WITHOUT ANY WARRANTY; without even the implied warranty of
  15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16 General Public License for more details.
  17
  18 Under Section 7 of GPL version 3, you are granted additional
  19 permissions described in the GCC Runtime Library Exception, version
  20 3.1, as published by the Free Software Foundation.
  21
  22 You should have received a copy of the GNU General Public License and
  23 a copy of the GCC Runtime Library Exception along with this program;
  24 see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
  25 <http://www.gnu.org/licenses/>.  *)
  26
  27 DEFINITION MODULE PushBackInput ;
  28
  29 FROM FIO IMPORT File ;
  30 FROM DynamicStrings IMPORT String ;
  31
  32 EXPORT QUALIFIED Open, PutCh, GetCh, Error, WarnError, WarnString,
  33                  Close, SetDebug, GetExitStatus, PutStr,
  34                  PutString, GetColumnPosition, GetCurrentLine ;
  35
  36
  37 (*
  38    Open - opens a file for reading.
  39 *)
  40
  41 PROCEDURE Open (a: ARRAY OF CHAR) : File ;
  42
  43
  44 (*
  45    GetCh - gets a character from either the push back stack or
  46            from file, f.
  47 *)
  48
  49 PROCEDURE GetCh (f: File) : CHAR ;
  50
  51
  52 (*
  53    PutCh - pushes a character onto the push back stack, it also
  54            returns the character which has been pushed.
  55 *)
  56
  57 PROCEDURE PutCh (ch: CHAR) : CHAR ;
  58
  59
  60 (*
  61    PutString - pushes a string onto the push back stack.
  62 *)
  63
  64 PROCEDURE PutString (a: ARRAY OF CHAR) ;
  65
  66
  67 (*
  68    PutStr - pushes a dynamic string onto the push back stack.
  69             The string, s, is not deallocated.
  70 *)
  71
  72 PROCEDURE PutStr (s: String) ;
  73
  74
  75 (*
  76    Error - emits an error message with the appropriate file, line combination.
  77 *)
  78
  79 PROCEDURE Error (a: ARRAY OF CHAR) ;
  80
  81
  82 (*
  83    WarnError - emits an error message with the appropriate file, line combination.
  84                It does not terminate but when the program finishes an exit status of
  85                1 will be issued.
  86 *)
  87
  88 PROCEDURE WarnError (a: ARRAY OF CHAR) ;
  89
  90
  91 (*
  92    WarnString - emits an error message with the appropriate file, line combination.
  93                 It does not terminate but when the program finishes an exit status of
  94                 1 will be issued.
  95 *)
  96
  97 PROCEDURE WarnString (s: String) ;
  98
  99
 100 (*
 101    Close - closes the opened file.
 102 *)
 103
 104 PROCEDURE Close (f: File) ;
 105
 106
 107 (*
 108    GetExitStatus - returns the exit status which will be 1 if any warnings were issued.
 109 *)
 110
 111 PROCEDURE GetExitStatus () : CARDINAL ;
 112
 113
 114 (*
 115    SetDebug - sets the debug flag on or off.
 116 *)
 117
 118 PROCEDURE SetDebug (d: BOOLEAN) ;
 119
 120
 121 (*
 122    GetColumnPosition - returns the column position of the current character.
 123 *)
 124
 125 PROCEDURE GetColumnPosition () : CARDINAL ;
 126
 127
 128 (*
 129    GetCurrentLine - returns the current line number.
 130 *)
 131
 132 PROCEDURE GetCurrentLine () : CARDINAL ;
 133
 134
 135 END PushBackInput.