#lang br (require brag/support) (define basic-lexer (lexer-srcloc [(eof) (return-without-srcloc eof)] [whitespace (token lexeme #:skip? #t)] [(from/to "rem" #\newline) (token 'REM lexeme)] [(:or "print" "goto" "end" "+" ":") lexeme] [(:+ numeric) (token 'INTEGER (string->number lexeme))] [(:or (:seq (:+ numeric) ".") (:seq (:* numeric) "." (:+ numeric))) (token 'DECIMAL (string->number lexeme))] [(from/to "\"" "\"") (token 'STRING (trim-ends "\"" lexeme "\""))])) (provide basic-lexer)