Changes to macro stepper (internal):
refactored context rep in steps to retain frame structure
fixed bug in syntax-restamp (bogus template, broke colors)
needs revisiting
svn: r5450
This commit is contained in:
Ryan Culpepper
parent
952a50906c
commit
9774e0926d
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@ -3,15 +3,24 @@
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(require "deriv.ss"
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"stx-util.ss"
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"steps.ss")
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(provide (all-defined)
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(all-from "steps.ss"))
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;; A Context is (syntax -> syntax)
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;; A BigContext is (list-of (cons Derivation (cons Syntaxes Syntax)))
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;; local expansion contexts: deriv, foci, term
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(provide (all-from "steps.ss"))
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(provide context
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big-context
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current-derivation
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with-context
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with-derivation
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with-new-local-context
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CC
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R
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revappend)
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(provide walk
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walk/foci
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stumble
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stumble/E)
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;; context: parameter of Context
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(define context (make-parameter (lambda (x) x)))
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(define context (make-parameter null))
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;; big-context: parameter of BigContext
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(define big-context (make-parameter null))
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@ -22,8 +31,8 @@
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(define-syntax with-context
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(syntax-rules ()
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[(with-context f . body)
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(let ([E (context)])
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(parameterize ([context (lambda (x) (E (f x)))])
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(let ([c (context)])
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(parameterize ([context (cons f c)])
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. body))]))
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(define-syntax with-derivation
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@ -34,15 +43,14 @@
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(define-syntax with-new-local-context
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(syntax-rules ()
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[(with-new-local-context e . body)
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(parameterize ([big-context
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(cons (cons (current-derivation) (cons (list e) (E e)))
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(parameterize ([big-context
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(cons (cons (current-derivation)
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(cons (list e)
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(context)))
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(big-context))]
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[context (lambda (x) x)])
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[context null])
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. body)]))
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;; E : syntax -> syntax
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(define (E stx) ((context) stx))
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;; -----------------------------------
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;; CC
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@ -83,15 +91,15 @@
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#'(let-values ([(form2-var foci1-var foci2-var description-var)
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(with-syntax ([p f])
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(values form2 foci1 foci2 description))])
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(cons (walk/foci/E foci1-var foci2-var f form2-var description-var)
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(cons (walk/foci foci1-var foci2-var f form2-var description-var)
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(R** form2-var p . more)))]
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[(R** f p [#:rename form2 foci1 foci2 description] . more)
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#'(let-values ([(form2-var foci1-var foci2-var description-var)
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(with-syntax ([p f])
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(values form2 foci1 foci2 description))])
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(cons (walk/foci/E foci1-var foci2-var
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f form2-var
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description-var)
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(cons (walk/foci foci1-var foci2-var
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f form2-var
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description-var)
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(R** form2-var p . more)))]
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[(R** f p [#:walk form2 description] . more)
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#'(let-values ([(form2-var description-var)
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@ -167,30 +175,26 @@
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;; -----------------------------------
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;; walk : syntax(s) syntax(s) StepType -> Reduction
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;; walk : syntax(es) syntax(es) StepType -> Reduction
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;; Lifts a local step into a term step.
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(define (walk e1 e2 type)
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(make-step (current-derivation) (big-context) type
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e1 e2 (E e1) (E e2)))
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;; walk/foci/E : syntax(s) syntax(s) syntax syntax StepType -> Reduction
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(define (walk/foci/E focus1 focus2 e1 e2 type)
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(walk/foci focus1 focus2 (E e1) (E e2) type))
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;; walk/foci : syntax(s) syntax(s) syntax syntax StepType -> Reduction
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(define (walk/foci focus1 focus2 Ee1 Ee2 type)
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(make-step (current-derivation) (big-context) type
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focus1 focus2 Ee1 Ee2))
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(make-step (current-derivation) (big-context) type (context)
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(foci e1) (foci e2) e1 e2))
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;; walk/foci : syntaxes syntaxes syntax syntax StepType -> Reduction
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(define (walk/foci foci1 foci2 Ee1 Ee2 type)
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(make-step (current-derivation) (big-context) type (context)
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(foci foci1) (foci foci2) Ee1 Ee2))
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;; stumble : syntax exception -> Reduction
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(define (stumble stx exn)
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(make-misstep (current-derivation) (big-context) 'error
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stx (E stx) exn))
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(make-misstep (current-derivation) (big-context) 'error (context)
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stx stx exn))
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;; stumble/E : syntax(s) syntax exn -> Reduction
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(define (stumble/E focus Ee1 exn)
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(make-misstep (current-derivation) (big-context) 'error
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(make-misstep (current-derivation) (big-context) 'error (context)
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focus Ee1 exn))
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;; ------------------------------------
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@ -198,4 +202,9 @@
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(define (revappend a b)
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(cond [(pair? a) (revappend (cdr a) (cons (car a) b))]
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[(null? a) b]))
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)
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(define (foci x)
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(if (list? x)
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x
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(list x)))
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)
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@ -140,9 +140,9 @@
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(with-syntax ([(?case-lambda [?formals . ?body] ...) e1]
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[((?formals* . ?body*) ...) (map car renames+bodies)])
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(let ([mid (syntax/skeleton e1 (?case-lambda [?formals* . ?body*] ...))])
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(cons (walk/foci/E (syntax->list #'(?formals ...))
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(syntax->list #'(?formals* ...))
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e1 mid 'rename-case-lambda)
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(cons (walk/foci (syntax->list #'(?formals ...))
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(syntax->list #'(?formals* ...))
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e1 mid 'rename-case-lambda)
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(R mid (CASE-LAMBDA [FORMALS . BODY] ...)
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[Block (BODY ...) (map cdr renames+bodies)]))))]
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[(AnyQ p:let-values (e1 e2 rs renames rhss body) exni)
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@ -391,9 +391,9 @@
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(stx-take tail
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(- (stx-improper-length tail)
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(stx-improper-length (stx-cdr suffix))))
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(E (revappend prefix
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(cons (deriv-e2 head) (stx-cdr suffix))))
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(E (revappend prefix tail))
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(revappend prefix
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(cons (deriv-e2 head) (stx-cdr suffix)))
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(revappend prefix tail)
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'splice-block))
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(cons (with-context (lambda (x)
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(revappend prefix (cons x (stx-cdr suffix))))
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@ -403,7 +403,7 @@
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;; FIXME
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(error 'unimplemented)]
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[(struct error-wrap (exn tag _inner))
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(values (list (stumble/E suffix (E (revappend prefix suffix)) exn))
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(values (list (stumble/E suffix (revappend prefix suffix) exn))
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(revappend prefix suffix))]))]
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[(null? brules)
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(values (apply append (reverse rss))
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@ -447,8 +447,8 @@
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(stx-take stxs
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(- (stx-improper-length stxs)
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(stx-improper-length suffix-tail)))
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(E (revappend prefix (cons head-e2 suffix-tail)))
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(E (revappend prefix stxs))
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(revappend prefix (cons head-e2 suffix-tail))
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(revappend prefix stxs)
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'splice-module)
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(loop next stxs prefix))))]
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[(struct mod:lift (head stxs))
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@ -459,8 +459,8 @@
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(let ([new-suffix (append stxs (cons head-e2 suffix-tail))])
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(cons (walk/foci null
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stxs
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(E (revappend prefix (cons head-e2 suffix-tail)))
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(E (revappend prefix new-suffix))
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(revappend prefix (cons head-e2 suffix-tail))
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(revappend prefix new-suffix)
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'splice-lifts)
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(loop next
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new-suffix
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@ -470,8 +470,8 @@
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(if (pair? tail)
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(list (walk/foci null
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tail
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(E (revappend prefix suffix))
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(E (revappend prefix tail))
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(revappend prefix suffix)
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(revappend prefix tail)
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'splice-module-lifts))
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null)
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(loop next tail prefix))]))]
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@ -1,20 +1,41 @@
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(module steps mzscheme
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(provide (all-defined))
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(require "deriv.ss")
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;; A ReductionSequence is a (list-of Reduction)
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;; A ProtoStep is (make-protostep Derivation BigContext StepType)
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;; A ProtoStep is (make-protostep Derivation BigContext StepType Context)
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;; A Context is a list of Frames
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;; A Frame is (syntax -> syntax)
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;; A BigContext is (list-of (cons Derivation (cons Syntaxes Syntax)))
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;; local expansion contexts: deriv, foci, term
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;; A Reduction is one of
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;; - (make-step ... Syntaxes Syntaxes Syntax Syntax)
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;; - (make-misstep ... Syntax Syntax Exception)
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(define-struct protostep (deriv lctx type) #f)
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(define-struct (step protostep) (redex contractum e1 e2) #f)
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(define-struct (misstep protostep) (redex e1 exn) #f)
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(define-struct protostep (deriv lctx type ctx) #f)
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(define-struct (step protostep) (foci1 foci2 e1 e2) #f)
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(define-struct (misstep protostep) (foci1 e1 exn) #f)
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;; context-fill : Context Syntax -> Syntax
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(define (context-fill ctx stx)
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(let loop ([ctx ctx] [stx stx])
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(if (null? ctx)
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stx
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(loop (cdr ctx) ((car ctx) stx)))))
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(define (step-term1 s)
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(context-fill (protostep-ctx s) (step-e1 s)))
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(define (step-term2 s)
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(context-fill (protostep-ctx s) (step-e2 s)))
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(define (misstep-term1 s)
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(context-fill (protostep-ctx s) (misstep-e1 s)))
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;; A StepType is a simple in the following alist.
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(define step-type-meanings
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@ -59,5 +80,40 @@
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(define (rewrite-step? x)
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(and (step? x) (not (rename-step? x))))
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(provide (all-defined))
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#;(begin
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(require (lib "contract.ss"))
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(provide rewrite-step?
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rename-step?)
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(provide/contract
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[step-type->string (any/c . -> . string?)]
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[step-term1 (step? . -> . syntax?)]
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[step-term2 (step? . -> . syntax?)]
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[misstep-term1 (misstep? . -> . syntax?)]
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[context-fill ((listof procedure?) syntax? . -> . syntax?)]
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(struct protostep
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([deriv deriv?]
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[lctx list?]
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[type (or/c symbol? boolean?)]
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[ctx (listof procedure?)]))
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(struct (step protostep)
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([deriv deriv?]
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[lctx list?]
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[type (or/c symbol? boolean?)]
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[ctx (listof procedure?)]
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[foci1 (listof syntax?)]
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[foci2 (listof syntax?)]
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[e1 syntax?]
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[e2 syntax?]))
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(struct (misstep protostep)
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([deriv deriv?]
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[lctx list?]
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[type (or/c symbol? boolean?)]
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[ctx (listof procedure?)]
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[foci1 (listof syntax?)]
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[e1 syntax?]
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[exn exn?])))
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)
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)
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@ -5,19 +5,10 @@
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(provide (all-defined)
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(all-from (lib "stx.ss" "syntax")))
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#;
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(define-syntax (CC stx)
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(syntax-case stx ()
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[(CC HOLE expr pattern)
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#'(lambda (in-the-hole)
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(with-syntax ([pattern expr])
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(with-syntax ([HOLE in-the-hole])
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#'pattern)))]))
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(define (d->so template datum)
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(let ([template (and (syntax? template) #f)])
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(datum->syntax-object template datum template template)))
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(if (syntax? template)
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(datum->syntax-object template datum template template)
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datum))
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(define-syntax (syntax-copier stx)
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(syntax-case stx ()
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@ -40,6 +31,7 @@
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[(syntax/restamp (pa (... ...)) new-expr old-expr)
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#`(let ([new-parts (stx->list new-expr)]
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[old-parts (stx->list old-expr)])
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#;
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(unless (= (length new-parts) (length old-parts))
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(printf "** syntax/restamp~n~s~n" (quote-syntax #,stx))
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(printf "pattern : ~s~n" (syntax-object->datum #'(pa (... ...))))
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@ -50,14 +42,6 @@
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(map (lambda (new old) (syntax/restamp pa new old))
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new-parts
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old-parts)))]
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#;[(syntax/restamp (pa ...) new-expr old-expr)
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(with-syntax ([(na ...) (generate-temporaries #'(pa ...))]
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[(oa ...) (generate-temporaries #'(pa ...))])
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#'(with-syntax ([(na ...) new-expr]
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[(oa ...) old-expr])
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(d->so
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old-expr
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(list (syntax/restamp pa #'na #'oa) ...))))]
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[(syntax/restamp (pa . pb) new-expr old-expr)
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#'(let ([na (stx-car new-expr)]
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[nb (stx-cdr new-expr)]
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@ -23,12 +23,12 @@
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;; trace : syntax -> Derivation
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(define (trace stx)
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(let-values ([(result tracer) (expand+tracer stx)])
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(let-values ([(result tracer) (expand+tracer stx expand)])
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(parse-derivation tracer)))
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;; trace/result : syntax -> (values syntax/exn Derivation)
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(define (trace/result stx)
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(let-values ([(result tracer) (expand+tracer stx)])
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(let-values ([(result tracer) (expand+tracer stx expand)])
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(values result
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(parse-derivation tracer))))
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@ -36,8 +36,8 @@
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(define (trace+reductions stx)
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(reductions (trace stx)))
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;; expand+tracer : syntax/sexpr -> (values syntax/exn (-> event))
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(define (expand+tracer sexpr)
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;; expand+tracer : syntax/sexpr (syntax -> A) -> (values A/exn (-> event))
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(define (expand+tracer sexpr expander)
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(let* ([s (make-semaphore 1)]
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[head (cons #f #f)]
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[tail head]
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@ -64,7 +64,7 @@
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(lambda (exn)
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(add! (cons 'error exn))
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exn)])
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(expand sexpr))])
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(expander sexpr))])
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(add! (cons 'EOF pos))
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(values result
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(lambda ()
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@ -64,15 +64,15 @@
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(cond [(step? step)
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(display (step-type->string (protostep-type step)))
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(newline)
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(show-term (step-e1 step) partition)
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(show-term (step-term1 step) partition)
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(display " ==>")
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(newline)
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(show-term (step-e2 step) partition)
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(show-term (step-term2 step) partition)
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(newline)]
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[(misstep? step)
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(display (exn-message (misstep-exn step)))
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(newline)
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(show-term (misstep-e1 step) partition)]))
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(show-term (misstep-term1 step) partition)]))
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(define (show-term stx partition)
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(define-values (datum flat=>stx stx=>flat)
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|
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@ -33,9 +33,12 @@
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;; Struct for one-by-one stepping
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(define-struct (prestep protostep) (redex e1))
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(define-struct (poststep protostep) (contractum e2))
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(define-struct (prestep protostep) (foci1 e1))
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(define-struct (poststep protostep) (foci2 e2))
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(define (prestep-term1 s) (context-fill (protostep-ctx s) (prestep-e1 s)))
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(define (poststep-term2 s) (context-fill (protostep-ctx s) (poststep-e2 s)))
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;; Macro Stepper
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(define view@
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|
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@ -387,7 +390,8 @@
|
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(define/private (update:show-lctx lctx)
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(when (pair? lctx)
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(for-each (lambda (bc)
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(send sbview add-text "While executing macro transformer in:\n")
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(send sbview add-text
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"While executing macro transformer in:\n")
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(insert-syntax/redex (cddr bc) (cadr bc)))
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lctx)
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(send sbview add-text "\n")))
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@ -399,34 +403,38 @@
|
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(insert-step-separator (step-type->string (protostep-type step))))
|
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|
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(define/private (update:separator/small step)
|
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(insert-step-separator/small (step-type->string (protostep-type step))))
|
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(insert-step-separator/small
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(step-type->string (protostep-type step))))
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||||
(define/private (update:show-step step)
|
||||
(update:show-protostep step)
|
||||
(insert-syntax/redex (step-e1 step) (foci (step-redex step)))
|
||||
(insert-syntax/redex (step-term1 step) (step-foci1 step))
|
||||
(update:separator step)
|
||||
(insert-syntax/contractum (step-e2 step) (foci (step-contractum step))))
|
||||
|
||||
(insert-syntax/contractum (step-term2 step) (step-foci2 step)))
|
||||
|
||||
(define/private (update:show-prestep step)
|
||||
(update:show-protostep step)
|
||||
(update:separator/small step)
|
||||
(insert-syntax/redex (prestep-e1 step) (foci (prestep-redex step))))
|
||||
(insert-syntax/redex (prestep-term1 step)
|
||||
(prestep-foci1 step)))
|
||||
|
||||
(define/private (update:show-poststep step)
|
||||
(update:show-protostep step)
|
||||
(update:separator/small step)
|
||||
(insert-syntax/contractum (poststep-e2 step) (foci (poststep-contractum step))))
|
||||
(insert-syntax/contractum (poststep-term2 step)
|
||||
(poststep-foci2 step)))
|
||||
|
||||
(define/private (update:show-misstep step)
|
||||
(update:show-protostep step)
|
||||
(insert-syntax/redex (misstep-e1 step) (foci (misstep-redex step)))
|
||||
(insert-syntax/redex (misstep-term1 step)
|
||||
(misstep-foci1 step))
|
||||
(update:separator step)
|
||||
(send sbview add-text (exn-message (misstep-exn step)))
|
||||
(send sbview add-text "\n")
|
||||
(when (exn:fail:syntax? (misstep-exn step))
|
||||
(for-each (lambda (e) (send sbview add-syntax e))
|
||||
(exn:fail:syntax-exprs (misstep-exn step)))))
|
||||
|
||||
|
||||
(define/private (update:show-final)
|
||||
(let ([result (lift/deriv-e2 synth-deriv)])
|
||||
(when result
|
||||
|
|
@ -438,7 +446,8 @@
|
|||
(define/private (update:show-suffix)
|
||||
(when (pair? derivs)
|
||||
(for-each (lambda (suffix-deriv)
|
||||
(send sbview add-syntax (lift/deriv-e1 suffix-deriv)))
|
||||
(send sbview add-syntax
|
||||
(lift/deriv-e1 suffix-deriv)))
|
||||
(cdr derivs))))
|
||||
|
||||
;; update/save-position : -> void
|
||||
|
|
@ -547,24 +556,8 @@
|
|||
;; At end; go to the end when restored
|
||||
(update-saved-position +inf.0)]
|
||||
[(protostep? step)
|
||||
(update-saved-position (extract-protostep-seq step))]))))
|
||||
|
||||
; ;; save-position : -> void
|
||||
; (define (save-position)
|
||||
; (define (steps-loop)
|
||||
; (let ([step (cursor:current steps)])
|
||||
; (cond [(not step)
|
||||
; ;; At end; go to the end when restored
|
||||
; +inf.0]
|
||||
; [(protostep? step)
|
||||
; (or (extract-protostep-seq step)
|
||||
; ;; Go one previous, if possible, and try again
|
||||
; (if (cursor:can-move-previous? steps)
|
||||
; (begin (cursor:move-previous steps)
|
||||
; (steps-loop))
|
||||
; #f))]
|
||||
; [else #f])))
|
||||
; (update-saved-position (and steps (steps-loop))))
|
||||
(update-saved-position
|
||||
(extract-protostep-seq step))]))))
|
||||
|
||||
;; restore-position : number -> void
|
||||
(define (restore-position)
|
||||
|
|
@ -640,13 +633,13 @@
|
|||
(define/private (reduce:one-by-one rs)
|
||||
(let loop ([rs rs])
|
||||
(match rs
|
||||
[(cons (struct step (d l t redex contractum e1 e2)) rs)
|
||||
(list* (make-prestep d l "Find redex" redex e1)
|
||||
(make-poststep d l t contractum e2)
|
||||
[(cons (struct step (d l t c redex contractum e1 e2)) rs)
|
||||
(list* (make-prestep d l "Find redex" c redex e1)
|
||||
(make-poststep d l t c contractum e2)
|
||||
(loop rs))]
|
||||
[(cons (struct misstep (d l t redex e1 exn)) rs)
|
||||
(list* (make-prestep d l "Find redex" redex e1)
|
||||
(make-misstep d l t redex e1 exn)
|
||||
[(cons (struct misstep (d l t c redex e1 exn)) rs)
|
||||
(list* (make-prestep d l "Find redex" c redex e1)
|
||||
(make-misstep d l t c redex e1 exn)
|
||||
(loop rs))]
|
||||
['()
|
||||
null])))
|
||||
|
|
|
|||
Loading…
Reference in New Issue
Block a user