racket/collects/tests/stxparse/test-exp.rkt
2011-05-02 21:02:11 -06:00

102 lines
3.0 KiB
Racket

#lang racket
(require rackunit
syntax/parse
syntax/parse/debug
syntax/parse/experimental/reflect
syntax/parse/experimental/splicing
syntax/parse/experimental/eh
syntax/parse/experimental/specialize
"setup.rkt"
(for-syntax syntax/parse))
;; Reflection
(define-syntax-class (nat> x)
#:description (format "natural number greater than ~s" x)
(pattern n:nat
#:when (> (syntax-e #'n) x)
#:with diff (- (syntax-e #'n) x)))
(define r-nat> (reify-syntax-class nat>))
(tok (1 2 -3 -4 5) ((~or (~reflect yes (r-nat> 1) #:attributes (diff)) no) ...)
(and (s= (yes ...) '(2 5))
(s= (yes.diff ...) '(1 4))
(s= (no ...) '(1 -3 -4))))
(terx 3 (~reflect pos (r-nat> 5))
#rx"expected natural number greater than 5")
(terx whatever (~reflect x (r-nat> 0) #:attributes (wrong nope)))
(define-splicing-syntax-class opt
(pattern (~seq #:a a:expr)))
(define r-opt (reify-syntax-class opt))
(tok (#:a 1) ((~splicing-reflect s (r-opt) #:attributes (a)))
(s= s.a '1))
(tok (#:a 1 #:a 2 #:a 3) ((~splicing-reflect s (r-opt) #:attributes (a)) ...)
(s= (s.a ...) '(1 2 3)))
;; EH-alternative-sets
(define-eh-alternative-set opts
(pattern (~once (~seq #:a a:expr) #:name "A option"))
(pattern (~seq #:b b:expr)))
(tok (#:a 1) ((~eh-var s opts) ...)
(and (s= s.a 1) (s= (s.b ...) '())))
(tok (#:a 1 #:b 2 #:b 3) ((~eh-var s opts) ...)
(and (s= s.a 1) (s= (s.b ...) '(2 3))))
(terx (#:b 2 #:b 3) ((~eh-var s opts) ...)
#rx"missing required occurrence of A option")
(terx (#:a 1 #:a 2) ((~eh-var s opts) ...)
#rx"too many occurrences of A option")
(define-eh-alternative-set extopts
(pattern (~eh-var s opts))
(pattern (~seq #:c c1:expr c2:expr)))
(tok (#:a 1 #:c 2 3 #:c 4 5) ((~eh-var x extopts) ...)
(and (s= x.s.a 1) (s= (x.s.b ...) '())
(s= ((x.c1 x.c2) ...) '((2 3) (4 5)))))
(terx (#:c 1 2) ((~eh-var x extopts) ...)
#rx"missing required occurrence of A option")
;; Splicing
(define-primitive-splicing-syntax-class (foo)
#:attributes (z x y)
#:description "foo"
(lambda (stx fail)
(syntax-case stx ()
[(a b c . rest)
(list 3 #'a #'b #'c)]
[_ (fail)])))
(tok (1 2 3 4) (f:foo 4)
(and (s= f.z 1) (s= f.x 2) (s= f.y 3)))
(terx (1) (f:foo)
#rx"expected foo")
;; Specialization
(define-syntax-class/specialize nat>10 (nat> 10))
(tok (11 23 45) (n:nat>10 ...))
(terx (11 10 9) (n:nat>10 ...)
#rx"expected natural number greater than 10")
(tcerr "specialize preserves #:no-delimit-cut"
(let ()
(define-syntax-class a #:no-delimit-cut (pattern _))
(define-syntax-class/specialize b a)
(syntax-parse #'12 [(~not x:b) (void)]))
#rx"syntax class with #:no-delimit-cut option not allowed within ~not pattern")
(test-case "specialize preserves lack of #:no-delimit-cut"
(let ()
(define-syntax-class a (pattern _:id))
(define-syntax-class/specialize b a)
(syntax-parse #'12 [(~not x:b) (void)])))