7491e172ea
The eopl language is now racket-based rather than mzscheme-based. This test-suite, which was originally distributed on the book's web-site has been re-written in the new language. Changes include dropping all drscheme-init.scm and top.scm files. Remaining files were renamed to use the .rkt extension and edited to use the #lang syntax (instead of modulue). Require and provide forms were changed to reflect racket's syntax instead of mzscheme's (eg, only-in vs. only). Several occurrences of one-armed ifs were changed to use when and unless. All tests have been run successfully.
93 lines
2.1 KiB
Racket
Executable File
93 lines
2.1 KiB
Racket
Executable File
#lang eopl
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;; grammar for the EXCEPTIONS language. This is a somewhat cut-down
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;; version of the LETREC language.
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;; exercise: allow the "list" operator to take expressions instead
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;; of just numbers.
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(provide (all-defined-out))
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;;;;;;;;;;;;;;;; grammatical specification ;;;;;;;;;;;;;;;;
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(define the-lexical-spec
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'((whitespace (whitespace) skip)
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(comment ("%" (arbno (not #\newline))) skip)
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(identifier
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(letter (arbno (or letter digit "_" "-" "?")))
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symbol)
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(number (digit (arbno digit)) number)
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(number ("-" digit (arbno digit)) number)
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))
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(define the-grammar
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'((program (expression) a-program)
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(expression (number) const-exp)
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(expression
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("-" "(" expression "," expression ")")
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diff-exp)
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(expression
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("if" expression "then" expression "else" expression)
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if-exp)
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(expression (identifier) var-exp)
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(expression
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("proc" "(" identifier ")" expression)
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proc-exp)
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(expression
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("(" expression expression ")")
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call-exp)
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(expression
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("let" identifier "=" expression "in" expression)
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let-exp)
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(expression
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("letrec"
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identifier "(" identifier ")" "=" expression
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"in" expression)
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letrec-exp)
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;; Lists. We will have lists of literal numbers only.
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(expression
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("list" "(" (separated-list number ",") ")")
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const-list-exp)
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(expression
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(unary-op "(" expression ")")
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unop-exp)
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(expression
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("try" expression "catch" "(" identifier ")" expression)
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try-exp)
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(expression
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("raise" expression)
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raise-exp)
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(unary-op ("null?") null?-unop)
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(unary-op ("car") car-unop)
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(unary-op ("cdr" ) cdr-unop)
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(unary-op ("zero?") zero?-unop)
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))
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;;;;;;;;;;;;;;;; sllgen boilerplate ;;;;;;;;;;;;;;;;
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(sllgen:make-define-datatypes the-lexical-spec the-grammar)
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(define show-the-datatypes
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(lambda () (sllgen:list-define-datatypes the-lexical-spec the-grammar)))
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(define scan&parse
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(sllgen:make-string-parser the-lexical-spec the-grammar))
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(define just-scan
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(sllgen:make-string-scanner the-lexical-spec the-grammar))
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