racket/collects/syntax/private/stxparse/parse.rkt
Ryan Culpepper eff9147ddc syntax/parse: literals, literal-sets, and phases (todo: docs)
typed-scheme: added missing import for literal
2010-05-04 14:12:49 -06:00

710 lines
29 KiB
Racket

#lang scheme/base
(require (for-syntax scheme/base
racket/private/sc
syntax/stx
syntax/id-table
syntax/keyword
unstable/syntax
"rep-data.ss"
"rep.ss"
"codegen-data.ss"
"../util/txlift.ss"
"../util.ss")
scheme/stxparam
scheme/list
syntax/stx
"runtime.ss"
"runtime-prose.ss")
(provide (all-defined-out))
(define-for-syntax (wash stx)
(syntax-e stx))
(define-for-syntax (wash-list washer stx)
(let ([l (stx->list stx)])
(unless l (raise-type-error 'wash-list "stx-list" stx))
(map washer l)))
(define-for-syntax (wash-iattr stx)
(with-syntax ([#s(attr name depth syntax?) stx])
(make-attr #'name (wash #'depth) (wash #'syntax?))))
(define-for-syntax (wash-sattr stx)
(with-syntax ([#s(attr name depth syntax?) stx])
(make-attr (wash #'name) (wash #'depth) (wash #'syntax?))))
(define-for-syntax (wash-iattrs stx)
(wash-list wash-iattr stx))
(define-for-syntax (wash-sattrs stx)
(wash-list wash-sattr stx))
;; ----
;; An FCE is expr[DFC]
;; (fail expr #:expect expr #:fce FCE) : expr
(define-syntax (fail stx)
(syntax-case stx ()
[(fail x #:expect p #:fce fce)
#'(enclosing-fail (make-failure x fce p))]))
;; ----
;; (parse:rhs RHS (SAttr ...) (id ...) id boolean)
;; : expr[(values ParseFunction DescriptionFunction)]
;; Takes a list of the relevant attrs; order is significant!
;; Returns either fail or a list having length same as 'relsattrs'
(define-syntax (parse:rhs stx)
(syntax-case stx ()
[(parse:rhs #s(rhs _ _ transparent? _ variants (def ...) commit?)
relsattrs (arg ...) get-description splicing?)
(with-syntax ([(k-param ...)
(if (syntax-e #'commit?)
#'()
#'(return))]
[k-ref/fail
(if (syntax-e #'commit?)
#'values
#'return)]
[k-ref/ok
(if (syntax-e #'commit?)
#'values
#'(lambda (result) (return (cons enclosing-fail result))))])
#| #`(with-error-collector
(make-parser
(lambda ___)
(collect-error)))
|#
#'(lambda (x k-param ... arg ...)
(define (fail-rhs failure)
(k-ref/fail
(expectation-of-thing (get-description arg ...)
transparent?
(if transparent? failure #f))))
def ...
(syntax-parameterize ((this-syntax (make-rename-transformer #'x)))
(with-enclosing-fail* fail-rhs
(parse:variants x relsattrs variants splicing? k-ref/ok)))))]))
;; (parse:variants id (SAttr ...) (Variant ...) boolean)
;; : expr[SyntaxClassResult]
(define-syntax (parse:variants stx)
(syntax-case stx ()
[(parse:variants x relsattrs (variant ...) splicing? k-ref)
#'(try (parse:variant x relsattrs variant splicing? k-ref) ...)]))
(define-syntax (parse:variant stx)
(syntax-case stx ()
[(parse:variant x relsattrs variant #f k-ref)
(with-syntax ([#s(variant _ _ pattern _ (def ...)) #'variant])
#`(let ([fc (dfc-empty x)])
def ...
(parse:S x fc pattern (variant-success x relsattrs variant () k-ref))))]
[(parse:variant x relsattrs variant #t k-ref)
(with-syntax ([#s(variant _ _ pattern _ (def ...)) #'variant])
#`(let ([fc (dfc-empty x)])
def ...
(parse:H x fc pattern rest index
(variant-success x relsattrs variant (rest index) k-ref))))]))
;; (variant-success id (SAttr ...) Variant (expr ...)) : expr[SyntaxClassResult]
(define-syntax (variant-success stx)
(syntax-case stx ()
[(variant-success x relsattrs #s(variant _ _ pattern sides _) (also ...) k-ref)
#`(convert-sides x sides
(base-success-expr #,(pattern-attrs (wash #'pattern))
relsattrs
(also ...)
k-ref))]))
;; (convert-sides id (Side ...) (m (IAttr ...) . MArgs)) : expr[X]
;; where (m (IAttr ...) MArgs) : expr[X]
(define-syntax (convert-sides stx)
(syntax-case stx ()
[(convert-sides x () kexpr)
#'kexpr]
[(convert-sides x (side0 . sides) (k iattrs . kargs))
(syntax-case #'side0 ()
[#s(clause:fail condition message)
#`(let* ([c (without-fails condition)]
[fc (dfc-add-post (dfc-empty x) (if (syntax? c) c x))])
(if c
(fail (if (syntax? c) c x)
#:expect (expectation-of-message message)
#:fce fc)
(convert-sides x sides (k iattrs . kargs))))]
[#s(clause:with pattern expr (def ...))
(with-syntax ([(p-iattr ...) (pattern-attrs (wash #'pattern))])
#`(let* ([y (datum->syntax #f (without-fails expr))]
[fc (dfc-add-post (dfc-empty x) y)])
def ...
(parse:S y fc pattern
(convert-sides x sides
(k (p-iattr ... . iattrs) . kargs)))))]
[#s(clause:attr a expr)
#`(let-attributes ([a (without-fails (check-list^depth a expr))])
(convert-sides x sides (k (a . iattrs) . kargs)))])]))
;; (base-success-expr (IAttr ...) (SAttr ...) (expr ...) : expr[SCResult]
(define-syntax (base-success-expr stx)
(syntax-case stx ()
[(base-success-expr iattrs relsattrs (also ...) k-ref)
(let ([reliattrs
(reorder-iattrs (wash-sattrs #'relsattrs)
(wash-iattrs #'iattrs))])
(with-syntax ([(#s(attr name _ _) ...) reliattrs])
#'(k-ref (list also ... (attribute name) ...))))]))
;; ----
;; (parse:clauses id (Clause ...))
(define-syntax (parse:clauses stx)
(syntax-case stx ()
[(parse:clauses x clauses ctx)
(with-disappeared-uses
(with-txlifts
(lambda ()
(define-values (chunks clauses-stx)
(parse-keyword-options #'clauses parse-directive-table
#:context #'ctx
#:no-duplicates? #t))
(define context
(options-select-value chunks '#:context #:default #'x))
(define-values (decls0 defs)
(get-decls+defs chunks #t #:context #'ctx))
(define (for-clause clause)
(syntax-case clause ()
[[p . rest]
(let-values ([(rest decls2 defs2 sides)
(parse-pattern-directives #'rest
#:allow-declare? #t
#:decls decls0
#:context #'ctx)])
(unless (and (stx-list? rest) (stx-pair? rest))
(raise-syntax-error #f
"expected non-empty clause body"
#'ctx
clause))
(with-syntax ([rest rest]
[pattern
(parse-whole-pattern #'p decls2 #:context #'ctx)]
[(local-def ...) defs2])
#`(let ([fc (dfc-empty x)])
local-def ...
(parse:S x fc pattern
(convert-sides x #,sides
(clause-success () (let () . rest)))))))]))
(unless (and (stx-list? clauses-stx) (stx-pair? clauses-stx))
(raise-syntax-error #f "expected non-empty sequence of clauses" #'ctx))
(with-syntax ([(def ...) (append (get-txlifts-as-definitions) defs)]
[(alternative ...)
(map for-clause (stx->list clauses-stx))])
#`(let ([fail (syntax-patterns-fail #,context)])
def ...
(with-enclosing-fail* fail
(try alternative ...)))))))]))
;; (clause-success (IAttr ...) expr) : expr
(define-syntax (clause-success stx)
(syntax-case stx ()
[(clause-success _ expr)
#'expr]))
;; ----
;; (parse:S id FCE SinglePattern expr) : expr
(define-syntax (parse:S stx)
(syntax-case stx ()
[(parse:S x fc pattern0 k)
(syntax-case #'pattern0 ()
[#s(internal-rest-pattern rest rest-fc)
#`(let ([rest x]
[rest-fc fc])
k)]
[#s(pat:name attrs pattern (name ...))
#`(let-attributes ([#s(attr name 0 #t) x] ...)
(parse:S x fc pattern k))]
[#s(pat:any attrs)
#'k]
[#s(pat:var _attrs name #f () () _)
#'(let-attributes ([#s(attr name 0 #t) x])
k)]
[#s(pat:var _attrs name parser (arg ...) (nested-a ...) commit?)
(with-syntax* ([(name-attr ...)
(if (identifier? #'name)
#'([#s(attr name 0 #t) x])
#'())]
[ok-e
#'(let-attributes (name-attr ...)
(let/unpack ((nested-a ...) result)
k))]
[fail-e
#'(fail x #:expect result #:fce fc)])
(if (syntax-e #'commit?)
#'(let ([result (parser x arg ...)])
(if (ok? result)
ok-e
fail-e))
#'(parser x
(lambda (result)
(if (ok? result)
(let ([fail-k (car result)]
[result (cdr result)])
(with-enclosing-fail fail-k
ok-e))
fail-e))
arg ...)))]
[#s(pat:datum attrs datum)
#`(let ([d (syntax->datum x)])
(if (equal? d (quote datum))
k
(fail x
#:expect (expectation pattern0)
#:fce fc)))]
[#s(pat:literal attrs literal input-phase lit-phase)
#`(if (and (identifier? x)
(free-identifier=?/phases x input-phase
(quote-syntax literal) lit-phase))
k
(fail x
#:expect (expectation pattern0)
#:fce fc))]
[#s(pat:ghost attrs ghost subpattern)
#'(parse:G x fc ghost (parse:S x fc subpattern k))]
[#s(pat:head attrs head tail)
#`(parse:H x fc head rest rest-fc
(parse:S rest rest-fc tail k))]
[#s(pat:dots attrs head tail)
#`(parse:dots x fc head tail k)]
[#s(pat:and attrs subpatterns)
(for/fold ([k #'k]) ([subpattern (reverse (syntax->list #'subpatterns))])
#`(parse:S x fc #,subpattern #,k))]
[#s(pat:or (a ...) (subpattern ...))
(with-syntax ([(#s(attr id _ _) ...) #'(a ...)])
#`(let ([success
(lambda (fail id ...)
(with-enclosing-fail fail
(let-attributes ([a id] ...) k)))])
(try (parse:S x fc subpattern
(disjunct subpattern success (enclosing-fail) (id ...)))
...)))]
[#s(pat:not () subpattern)
#`(let ([fail-to-succeed (lambda (_failure) k)]
[outer-fail enclosing-fail])
(with-enclosing-fail* fail-to-succeed
(parse:S x fc subpattern
(with-enclosing-fail outer-fail
(fail x #:expect (expectation pattern0) #:fce fc)))))]
[#s(pat:compound attrs kind0 (part-pattern ...))
(let ([kind (get-kind (wash #'kind0))])
(with-syntax ([(part ...) (generate-temporaries (kind-selectors kind))])
(with-syntax ([predicate (kind-predicate kind)]
[(part-fc ...) (generate-temporaries #'(part ...))]
[(part-fc-proc ...) (kind-frontier-procs kind)]
[(part-expr ...)
(for/list ([selector (kind-selectors kind)])
(selector #'x #'datum))])
#`(let ([datum (syntax-e x)])
(if (predicate datum)
(let ([part part-expr] ...)
(let ([part-fc (part-fc-proc fc part)] ...)
(parse:S* (part ...) (part-fc ...) (part-pattern ...) k)))
(fail x
#:expect (expectation pattern0)
#:fce fc))))))]
[#s(pat:describe attrs description transparent? pattern)
#`(let ([previous-fail enclosing-fail]
[previous-cut-fail enclosing-cut-fail])
(define (new-fail failure)
(fail x
#:expect (expectation-of-thing description transparent? failure)
#:fce fc))
(with-enclosing-fail* new-fail
(let ([new-fc (dfc-empty x)])
(parse:S x new-fc pattern
(with-enclosing-cut-fail previous-cut-fail
(with-enclosing-fail previous-fail
k))))))])]))
;; (parse:S* (id ...) (FCE ...) (SinglePattern ...) expr) : expr
(define-syntax parse:S*
(syntax-rules ()
[(parse:S* () () () k)
k]
[(parse:S* (part0 . parts) (fc0 . fcs) (pattern0 . patterns) k)
(parse:S part0 fc0 pattern0 (parse:S* parts fcs patterns k))]))
;; (disjunct Pattern id (expr ...) (id ...)) : expr
(define-syntax (disjunct stx)
(syntax-case stx ()
[(disjunct pattern success (pre ...) (id ...))
(with-syntax ([(#s(attr sub-id _ _) ...) (pattern-attrs (wash #'pattern))])
(with-syntax ([(alt-sub-id ...) (generate-temporaries #'(sub-id ...))])
#`(let ([alt-sub-id (attribute sub-id)] ...)
(let ([id #f] ...)
(let ([sub-id alt-sub-id] ...)
(success pre ... id ...))))))]))
;; (disjunct (clause:attr ...) id (expr ...) (id ...)) : expr
(define-syntax (disjunct/sides stx)
(syntax-case stx ()
[(disjunct/sides clauses success (pre ...) (id ...))
(with-syntax ([(#s(clause:attr #s(attr sub-id _ _) _) ...) #'clauses])
(with-syntax ([(alt-sub-id ...) (generate-temporaries #'(sub-id ...))])
#`(let ([alt-sub-id (attribute sub-id)] ...)
(let ([id #f] ...)
(let ([sub-id alt-sub-id] ...)
(success pre ... id ...))))))]))
;; (parse:G id FCE SinglePattern expr) : expr
(define-syntax (parse:G stx)
(syntax-case stx ()
[(parse:G x fc pattern0 k)
(syntax-case #'pattern0 ()
[#s(ghost:cut _)
#`(with-enclosing-fail enclosing-cut-fail k)]
[#s(ghost:bind _ clauses)
#`(convert-sides x clauses (clause-success () k))]
[#s(ghost:fail _ early? condition message)
#`(let* ([c (without-fails condition)]
[fc* (if (quote early?)
fc
(dfc-add-post fc (if (syntax? c) c x)))])
(if c
(fail (if (syntax? c) c x)
#:expect (expectation pattern0)
#:fce fc*)
k))]
[#s(ghost:parse _ pattern expr)
#`(let* ([y (datum->syntax #f (without-fails expr))]
[fc* (dfc-add-post fc y)])
(parse:S y fc* pattern k))])]))
(begin-for-syntax
;; convert-list-pattern : ListPattern id -> SinglePattern
;; Converts '() datum pattern at end of list to bind (cons stx index)
;; to rest-var.
(define (convert-list-pattern pattern end-pattern)
(syntax-case pattern ()
[#s(pat:datum () ())
end-pattern]
[#s(pat:name attrs pattern names)
(with-syntax ([pattern (convert-list-pattern #'pattern end-pattern)])
#'#s(pat:name attrs pattern names))]
[#s(pat:ghost attrs ghost tail)
(with-syntax ([tail (convert-list-pattern #'tail end-pattern)])
#'#s(pat:ghost attrs ghost tail))]
[#s(pat:head attrs head tail)
(with-syntax ([tail (convert-list-pattern #'tail end-pattern)])
#'#s(pat:head attrs head tail))]
[#s(pat:dots attrs head tail)
(with-syntax ([tail (convert-list-pattern #'tail end-pattern)])
#'#s(pat:dots attrs head tail))]
[#s(pat:compound attrs #:pair (head-part tail-part))
(with-syntax ([tail-part (convert-list-pattern #'tail-part end-pattern)])
#'#s(pat:compound attrs #:pair (head-part tail-part)))])))
;; (parse:H id FCE HeadPattern id id expr) : expr
;; x must not alias rest
(define-syntax (parse:H stx)
(syntax-case stx ()
[(parse:H x fc head rest rest-fc k)
(syntax-case #'head ()
[#s(hpat:describe _ description transparent? pattern)
#`(let ([previous-fail enclosing-fail]
[previous-cut-fail enclosing-cut-fail])
(define (new-fail failure)
(fail x
#:expect (expectation-of-thing description transparent? failure)
#:fce fc))
(let ([fc* (dfc-empty x)])
(with-enclosing-fail* new-fail
(parse:H x fc* pattern rest rest-fc
(with-enclosing-cut-fail previous-cut-fail
(with-enclosing-fail previous-fail
k))))))]
[#s(hpat:var _attrs name parser (arg ...) (nested-a ...) commit?)
(with-syntax* ([(name-attr ...)
(if (identifier? #'name)
#'([#s(attr name 0 #t)
(stx-list-take x (dfc->index local-fc))])
#'())]
[ok-e
#'(let* ([rest (car result)]
[local-fc (cadr result)]
[rest-fc (dfc-append fc local-fc)])
(let-attributes (name-attr ...)
(let/unpack ((nested-a ...) (cddr result))
k)))]
[fail-e
#'(fail x #:expect result #:fce fc)])
(if (syntax-e #'commit?)
#'(let ([result (parser x arg ...)])
(if (ok? result)
ok-e
fail-e))
#'(parser x
(lambda (result)
(if (ok? result)
(let ([fail-k (car result)]
[result (cdr result)])
(with-enclosing-fail fail-k
ok-e))
fail-e))
arg ...)))]
[#s(hpat:and (a ...) head single)
#`(parse:H x fc head rest rest-fc
(let ([lst (stx-list-take x (dfc-difference fc rest-fc))])
(parse:S lst fc single k)))]
[#s(hpat:or (a ...) (subpattern ...))
(with-syntax ([(#s(attr id _ _) ...) #'(a ...)])
#`(let ([success
(lambda (rest rest-fc fail id ...)
(with-enclosing-fail fail
(let-attributes ([a id] ...) k)))])
(try (parse:H x fc subpattern rest rest-fc
(disjunct subpattern success
(rest rest-fc enclosing-fail) (id ...)))
...)))]
[#s(hpat:seq attrs pattern)
(with-syntax ([pattern
(convert-list-pattern
#'pattern
#'#s(internal-rest-pattern rest rest-fc))])
#'(parse:S x fc pattern k))]
[#s(hpat:optional (a ...) pattern defaults)
(with-syntax ([(#s(attr id _ _) ...) #'(a ...)])
#`(let ([success
(lambda (rest rest-fc fail id ...)
(with-enclosing-fail fail
(let-attributes ([a id] ...) k)))])
(try (parse:H x fc pattern rest rest-fc
(success rest rest-fc enclosing-fail (attribute id) ...))
(let ([rest x]
[rest-fc fc])
(convert-sides x defaults
(clause-success ()
(disjunct/sides defaults success
(rest rest-fc enclosing-fail)
(id ...))))))))]
[_
(with-syntax ([attrs (pattern-attrs (wash #'head))])
#'(parse:S x fc
#s(pat:compound attrs
#:pair
(head #s(internal-rest-pattern rest rest-fc)))
k))])]))
;; (parse:dots id FCE EHPattern SinglePattern expr) : expr
(define-syntax (parse:dots stx)
(syntax-case stx ()
[(parse:dots x fc (#s(ehpat head-attrs head head-repc) ...) tail k)
(let ()
(define repcs (wash-list wash #'(head-repc ...)))
(define rep-ids (for/list ([repc repcs])
(and repc (generate-temporary 'rep))))
(define rel-repcs (filter values repcs))
(define rel-rep-ids (filter values rep-ids))
(define aattrs
(for/list ([head-attrs (syntax->list #'(head-attrs ...))]
[repc repcs]
#:when #t
[a (wash-iattrs head-attrs)])
(cons a repc)))
(define attrs (map car aattrs))
(define attr-repcs (map cdr aattrs))
(define ids (map attr-name attrs))
(with-syntax ([(id ...) ids]
[(alt-id ...) (generate-temporaries ids)]
[reps rel-rep-ids]
[(head-rep ...) rep-ids]
[(rel-rep ...) rel-rep-ids]
[(rel-repc ...) rel-repcs]
[(a ...) attrs]
[(attr-repc ...) attr-repcs])
(define-pattern-variable alt-map #'((id . alt-id) ...))
(define-pattern-variable loop-k
#'(dots-loop dx* loop-fc* enclosing-fail rel-rep ... alt-id ...))
#`(let ()
(define (dots-loop dx loop-fc loop-fail rel-rep ... alt-id ...)
(with-enclosing-fail loop-fail
(try (parse:EH dx loop-fc head head-repc dx* loop-fc* alt-map head-rep
loop-k)
...
(cond [(< rel-rep (rep:min-number rel-repc))
(fail dx
#:expect (expectation-of-reps/too-few rel-rep rel-repc)
#:fce (dfc-add-pre loop-fc #f))]
...
[else
(let-attributes ([a (rep:finalize a attr-repc alt-id)] ...)
(parse:S dx loop-fc tail k))]))))
(let ([rel-rep 0] ...
[alt-id (rep:initial-value attr-repc)] ...)
(dots-loop x fc enclosing-fail rel-rep ... alt-id ...)))))]))
;; (parse:EH id FCE EHPattern id id ((id . id) ...)
;; RepConstraint/#f expr) : expr
(define-syntax (parse:EH stx)
(syntax-case stx ()
[(parse:EH x fc head repc x* fc* alts rep k0)
(let ()
(define-pattern-variable k
(let* ([main-attrs (wash-iattrs (pattern-attrs (wash #'head)))]
[ids (map attr-name main-attrs)]
[alt-ids
(let ([table (make-bound-id-table)])
(for ([entry (syntax->list #'alts)])
(let ([entry (syntax-e entry)])
(bound-id-table-set! table (car entry) (cdr entry))))
(for/list ([id ids]) (bound-id-table-ref table id)))])
(with-syntax ([(id ...) ids]
[(alt-id ...) alt-ids]
[(alt-a ...) (map rename-attr main-attrs alt-ids)])
#`(let ([alt-id (rep:combine repc (attribute id) alt-id)] ...)
k0))))
(syntax-case #'repc ()
[#f #`(parse:H x fc head x* fc* k)]
[_ #`(parse:H x fc head x* fc*
(if (< rep (rep:max-number repc))
(let ([rep (add1 rep)]) k)
(fail x*
#:expect (expectation-of-reps/too-many rep repc)
#:fce fc*)))]))]))
;; (rep:initial-value RepConstraint) : expr
(define-syntax (rep:initial-value stx)
(syntax-case stx ()
[(_ #s(rep:once _ _ _)) #'#f]
[(_ #s(rep:optional _ _ _)) #'#f]
[(_ _) #'null]))
;; (rep:finalize RepConstraint expr) : expr
(define-syntax (rep:finalize stx)
(syntax-case stx ()
[(_ a #s(rep:optional _ _ defaults) v)
(with-syntax ([#s(attr name _ _) #'a]
[(#s(clause:attr da de) ...) #'defaults])
(let ([default
(for/or ([da (syntax->list #'(da ...))]
[de (syntax->list #'(de ...))])
(with-syntax ([#s(attr dname _ _) da])
(and (bound-identifier=? #'name #'dname) de)))])
(if default
#`(or v #,default)
#'v)))]
[(_ a #s(rep:once _ _ _) v) #'v]
[(_ a _ v) #'(reverse v)]))
;; (rep:min-number RepConstraint) : expr
(define-syntax (rep:min-number stx)
(syntax-case stx ()
[(_ #s(rep:once _ _ _)) #'1]
[(_ #s(rep:optional _ _ _)) #'0]
[(_ #s(rep:bounds min max _ _ _)) #'min]))
;; (rep:max-number RepConstraint) : expr
(define-syntax (rep:max-number stx)
(syntax-case stx ()
[(_ #s(rep:once _ _ _)) #'1]
[(_ #s(rep:optional _ _ _)) #'1]
[(_ #s(rep:bounds min max _ _ _)) #'max]))
;; (rep:combine RepConstraint expr expr) : expr
(define-syntax (rep:combine stx)
(syntax-case stx ()
[(_ #s(rep:once _ _ _) a b) #'a]
[(_ #s(rep:optional _ _ _) a b) #'a]
[(_ _ a b) #'(cons a b)]))
;; ----
;; (expectation Pattern)
(define-syntax (expectation stx)
(syntax-case stx ()
[(_ #s(pat:datum attrs d))
#'(begin (collect-error '(datum d))
(make-expect:atom 'd))]
[(_ #s(pat:literal attrs lit input-phase lit-phase))
#'(begin (collect-error '(literal lit))
(make-expect:literal (quote-syntax lit)))]
;; 2 pat:compound patterns
;;[(_ #s(pat:compound attrs #:pair (head-pattern tail-pattern)))
;; #'(make-expect:pair)]
[(_ #s(pat:compound attrs kind0 (part-pattern ...)))
#'(collect-error 'ineffable)]
[(_ #s(pat:not _ pattern))
#'(collect-error 'ineffable)]
[(_ #s(ghost:fail _ _e condition message))
#'(expectation-of-message message)]))
;; ----
(define-syntax-rule (expectation-of-thing description transparent? chained)
(make-expect:thing description transparent? chained))
(define-syntax-rule (expectation-of-message message)
(let ([msg (collect-error message)])
(if msg
(make-expect:message msg)
'ineffable)))
(define-syntax expectation-of-reps/too-few
(syntax-rules ()
[(_ rep #s(rep:once name too-few-msg too-many-msg))
(expectation-of-message/too-few too-few-msg name)]
[(_ rep #s(rep:optional name too-many-msg _))
(error 'impossible)]
[(_ rep #s(rep:bounds min max name too-few-msg too-many-msg))
(expectation-of-message/too-few too-few-msg name)]))
(define-syntax expectation-of-reps/too-many
(syntax-rules ()
[(_ rep #s(rep:once name too-few-msg too-many-msg))
(expectation-of-message/too-many too-many-msg name)]
[(_ rep #s(rep:optional name too-many-msg _))
(expectation-of-message/too-many too-many-msg name)]
[(_ rep #s(rep:bounds min max name too-few-msg too-many-msg))
(expectation-of-message/too-many too-many-msg name)]))
(define-syntax expectation-of-message/too-few
(syntax-rules ()
[(emtf #f #f)
(expectation-of-message "repetition constraint violated")]
[(emtf #f name)
(expectation-of-message
(format "missing required occurrence of ~a" name))]
[(emtf msg _)
(expectation-of-message msg)]))
(define-syntax expectation-of-message/too-many
(syntax-rules ()
[(emtm #f #f)
(expectation-of-message
(format "repetition constraint violated"))]
[(emtm #f name)
(expectation-of-message
(format "too many occurrences of ~a" name))]
[(emtm msg _)
(expectation-of-message msg)]))
;;
(define-syntax-parameter collect-error
(syntax-rules ()
[(ce thing) thing]
[(ce) '()]))
(define-syntax-rule (with-error-collector body)
(...
(let-syntax ([tmp (box null)])
(syntax-parameterize ((collect-error
(lambda (stx)
(let ([b (syntax-local-value #'tmp)])
(syntax-case stx ()
[(ce thing)
(begin (set-box! b (cons #'thing (unbox b)))
#'thing)]
[(ce)
(with-syntax ([(thing ...) (reverse (unbox b))])
#'(list #'thing ...))])))))
body))))