Plex and Pyacc
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Revision as of 08:13, 13 August 2010 by Sekelsenmat (talk | contribs) (New page: Free Pascal comes with substitutes for the GNU projects Lex and YACC. They are called Plex and Pyacc and they can be used to generate compilers and regular expression analyzers in Pascal i...)
Free Pascal comes with substitutes for the GNU projects Lex and YACC. They are called Plex and Pyacc and they can be used to generate compilers and regular expression analyzers in Pascal instead of C.
Library contents
TP Lex and Yacc can be found here: http://svn.freepascal.org/cgi-bin/viewvc.cgi/trunk/utils/tply/
Documentation
Download the manual here: http://svn.freepascal.org/cgi-bin/viewvc.cgi/trunk/utils/tply/tply.doc?revision=1
Simple example application
This is a very simple calculator, which shows how to use plex and pyacc. The files in this simple project are:
- build.sh
- lexer.l
- parser.y
build.sh
<delphi> </delphi>
lexer.l
<delphi> </delphi>
parser.y
<delphi>
</delphi>
How to use it
Type for example: 5+3=
And it will answer with: 8
You can also try 3*8=H to request an answer in Hexadecimal instead of decimal
