(module lex-plt-v200 mzscheme (require br-parser-tools/lex (prefix : br-parser-tools/lex-sre)) (provide epsilon ~ (rename :* *) (rename :+ +) (rename :? ?) (rename :or :) (rename :& &) (rename :: @) (rename :~ ^) (rename :/ -)) (define-lex-trans epsilon (syntax-rules () ((_) ""))) (define-lex-trans ~ (syntax-rules () ((_ re) (complement re)))))