-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 I've just completed a small example for a logo like language using the parser tools. Take a look at files mech.rkt and test-mech.rkt here: http://github.com/ebellani/robo
If you have any doubts just ask. On 10/12/2010 03:12 PM, Mark Carter wrote: > Are there any examples on using lex and yacc, as I'm having trouble getting > started. I am trying to write a simple calculator. Here's what I've got so > far: > > #lang racket/base > > (require parser-tools/lex) > > (define lex (lexer > ((:+ "[0-9]") (values 'int (string->number lexeme))) > ((:+ whitespace) null) > ((:: "+") (values 'plus 0)) > ((:: "-") (values 'minus 0)) > ((:: "*") (values 'mult 0)) > ((:: "/") (values 'div 0)))) > > When I try to compile it, I get > regular-expression: undefined operator in: (:+ "[0-9]") > How do I correct this? > > > > > _________________________________________________ > For list-related administrative tasks: > http://lists.racket-lang.org/listinfo/users - -- Eduardo Bellani omnia mutantur, nihil interit. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iEYEARECAAYFAky4sOEACgkQSbLl0kCTjGkhewCePnzwLnlvzK/hVxKawsMIiqhx z5YAn23BpOnmpaxiasgBAHq+1t7qCXix =HkOP -----END PGP SIGNATURE----- _________________________________________________ For list-related administrative tasks: http://lists.racket-lang.org/listinfo/users
