lex & yacc, 2nd Edition

Appendix G. Abraxas lex and yacc

Abraxas Software offers pcyacc, which contains pcyacc and pclex, MS-DOS and OS/2 versions of yacc and lex. It is available from:

         Abraxas Software          7033 SW Macadam Avenue          Portland OR 97219          Phone: [phone]       

Pclex is based on flex, so much of what we have said about flex also applies to pclex.

Differences

• The output files have different names: lex_yy.c, yytab.c, yytab.h, and yy.lrt. rather than lex.yy.c, y.tab.c, y.tab.h, and y.output.

• The standard lex input buffer is only 256 characters. You can enlarge it by redefining some macros. See "yytext" in Chapter 6.

New Features

• An option lets you just check the syntax of a yacc specification rather than waiting for it to generate a complete parser.

• Each time it reduces a rule, a parser can write a line with the symbols in that rule into a file. (Abraxas refers to this as the parse tree option.)

• An optional extended error recovery library allows more complete error reporting and recovery.

• The package includes sample scanners and parsers for ANSI and K&R C, C++, Cobol, dBase III and IV, Fortran, Hypertalk, Modula-2, Pascal, pic (a demo language unrelated to troff), Postscript, Prolog, Smalltalk, SQL, and yacc and lex themselves.