gcc/m2/gm2-libs-iso/StringChan.mod

   1 (* StringChan.mod implements String input/output over channels.
   2
   3 Copyright (C) 2009-2024 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 IMPLEMENTATION MODULE StringChan ;
  28
  29
  30 FROM DynamicStrings IMPORT Length, char ;
  31 FROM TextIO IMPORT WriteChar ;
  32
  33
  34 (*
  35    writeString - writes a string, s, to ChanId, cid.
  36                  The string, s, is not destroyed.
  37 *)
  38
  39 PROCEDURE writeString (cid: IOChan.ChanId; s: String) ;
  40 VAR
  41    i, h: CARDINAL ;
  42 BEGIN
  43    h := Length(s) ;
  44    i := 0 ;
  45    WHILE i<h DO
  46       WriteChar(cid, char(s, i)) ;
  47       INC(i)
  48    END
  49 END writeString ;
  50
  51
  52 (*
  53    writeFieldWidth - writes a string, s, to ChanId, cid.
  54                      The string, s, is not destroyed and it
  55                      is prefixed by spaces so that at least,
  56                      width, characters are written.  If the
  57                      string, s, is longer than width then
  58                      no spaces are prefixed to the output
  59                      and the entire string is written.
  60 *)
  61
  62 PROCEDURE writeFieldWidth (cid: IOChan.ChanId;
  63                            s: String; width: CARDINAL) ;
  64 VAR
  65    i: CARDINAL ;
  66 BEGIN
  67    i := Length(s) ;
  68    WHILE i<width DO
  69       WriteChar(cid, ' ') ;
  70       INC(i)
  71    END ;
  72    writeString(cid, s)
  73 END writeFieldWidth ;
  74
  75
  76 END StringChan.