gcc/m2/gm2-libs/Scan.def

   1 (* Scan.def Provides a primitive symbol fetching from 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 Scan ;
  28
  29 (* Provides a primitive symbol fetching from input.
  30    Symbols are delimited by spaces and tabs.
  31    Limitation only allows one source file at
  32    a time to deliver symbols.  *)
  33
  34
  35 EXPORT QUALIFIED GetNextSymbol, WriteError,
  36                  OpenSource, CloseSource,
  37                  TerminateOnError, DefineComments ;
  38
  39
  40 (* OpenSource - opens a source file for reading.                  *)
  41
  42 PROCEDURE OpenSource (a: ARRAY OF CHAR) : BOOLEAN ;
  43
  44
  45 (* CloseSource - closes the current source file from reading.     *)
  46
  47 PROCEDURE CloseSource ;
  48
  49
  50 (* GetNextSymbol gets the next source symbol and returns it in a. *)
  51
  52 PROCEDURE GetNextSymbol (VAR a: ARRAY OF CHAR) ;
  53
  54
  55 (* WriteError writes a message, a, under the source line, which   *)
  56 (* attempts to pinpoint the Symbol at fault.                      *)
  57
  58 PROCEDURE WriteError (a: ARRAY OF CHAR) ;
  59
  60
  61 (*
  62    TerminateOnError - exits with status 1 if we call WriteError.
  63 *)
  64
  65 PROCEDURE TerminateOnError ;
  66
  67
  68 (*
  69    DefineComments - defines the start of comments within the source
  70                     file.
  71
  72                     The characters in Start define the comment start
  73                     and characters in End define the end.
  74                     The BOOLEAN eoln determine whether the comment
  75                     is terminated by end of line. If eoln is TRUE
  76                     then End is ignored.
  77
  78                     If this procedure is never called then no comments
  79                     are allowed.
  80 *)
  81
  82 PROCEDURE DefineComments (Start, End: ARRAY OF CHAR; eoln: BOOLEAN) ;
  83
  84
  85 END Scan.