racket/collects/macro-debugger/model/deriv-util.ss
Ryan Culpepper 3fe785014a Macro stepper: minor bug fix
svn: r5460
2007-01-25 19:16:14 +00:00

250 lines
7.4 KiB
Scheme

(module deriv-util mzscheme
(require "deriv.ss"
(lib "list.ss")
(lib "plt-match.ss"))
(provide IntW
ErrW
AnyQ
IntQ
Wrap
lift/wrap
rewrap
rewrap/nt
outer-rewrap
lift/deriv-e1
lift/deriv-e2
wrapped?
find-derivs
find-deriv
find-derivs/syntax)
;; IntW
;; Matches only interrupted wraps
(define-match-expander IntW
(syntax-rules ()
[(IntW S (var ...))
(struct interrupted-wrap (_ (struct S (var ...))))]
[(IntW S (var ...) tag)
(struct interrupted-wrap (tag (struct S (var ...))))]))
;; ErrW
;; Matches only error wraps
(define-match-expander ErrW
(syntax-rules ()
[(ErrW S (var ...))
(struct error-wrap (_ _ (struct S (var ...))))]
[(ErrW S (var ...) exn)
(struct error-wrap (exn _ (struct S (var ...))))]
[(ErrW S (var ...) tag exn)
(struct error-wrap (exn tag (struct S (var ...))))]))
;; AnyQ matcher
;; Matches unwrapped, interrupted wrapped, or error wrapped
(define-match-expander AnyQ
(syntax-rules ()
[(AnyQ S (var ...))
(app unwrap (struct S (var ...)))]
[(AnyQ S (var ...) exni)
(and (app unwrap (struct S (var ...)))
(app extract-exni exni))]))
;; IntQ
;; Matches interrupted wraps and unwrapped structs
(define-match-expander IntQ
(syntax-rules ()
[(IntQ S (var ...))
(? not-error-wrap? (app unwrap (struct S (var ...))))]
[(IntQ S (var ...) tag)
(? not-error-wrap?
(app unwrap (struct S (var ...)))
(app extract-tag tag))]))
(define-match-expander Wrap
(syntax-rules ()
[(Wrap x)
(app unwrap x)]))
(define (unwrap x)
(match x
[(struct interrupted-wrap (tag inner))
inner]
[(struct error-wrap (exn tag inner))
inner]
[else x]))
(define (extract-exni x)
(match x
[(struct interrupted-wrap (tag inner))
(cons #f tag)]
[(struct error-wrap (exn tag inner))
(cons exn tag)]
[else #f]))
(define (extract-tag x)
(match x
[(struct interrupted-wrap (tag inner))
tag]
[(struct error-wrap (exn tag inner))
tag]
[else #f]))
(define (not-error-wrap? x)
(not (error-wrap? x)))
;; lift/wrap : ('a -> 'b) boolean -> Wrap('a) -> Wrap('b)
(define (lift/wrap f preserve-tag?)
(lambda (x)
(match x
[(struct interrupted-wrap (tag inner))
(make-interrupted-wrap (and preserve-tag? tag) (f inner))]
[(struct error-wrap (exn tag inner))
(make-error-wrap exn (and preserve-tag? tag) (f inner))]
[x
(f x)])))
;; rewrap : Wrap('a) 'b -> Wrap('b)
(define (rewrap x y)
(if (wrapped? y)
y
((lift/wrap (lambda (x) y) #t) x)))
;; rewrap/nt : Wrap('a) 'b -> Wrap('b)
(define (rewrap/nt x y)
(if (wrapped? y)
y
((lift/wrap (lambda (x) y) #f) x)))
(define (outer-rewrap x y)
(if (and (wrapped? x) (not (wrapped? y)))
(make-interrupted-wrap #f y)
y))
(define (lift/deriv-e1 x)
(match x
[(AnyQ deriv (e1 _)) e1]))
(define (lift/deriv-e2 x)
(match x
[(AnyQ deriv (_ e2)) e2]))
(define (wrapped? x)
(or (interrupted-wrap? x)
(error-wrap? x)))
;; Utilities for finding subderivations
;; find-derivs : (deriv -> boolean) (deriv -> boolean) deriv -> (list-of deriv)
(define (find-derivs pred stop-short d)
(find-deriv/unit+join+zero pred stop-short d list append null))
;; find-deriv : (deriv -> boolean) (deriv -> boolean) deriv -> deriv/#f
;; Finds the first deriv that matches; throws the rest away
(define (find-deriv pred stop-short d)
(let/ec return (find-deriv/unit+join+zero pred stop-short d return (lambda _ #f) #f)))
;; find-deriv/unit+join+zero
;; Parameterized over monad operations for combining the results
;; For example, <list, append, null> collects the results into a list
(define (find-deriv/unit+join+zero pred stop-short d unit join zero)
(define (loop d)
(match d
[(? pred d) (unit d)]
[(? stop-short d) zero]
[(AnyQ mrule (_ _ tx next))
(join (loop tx) (loop next))]
[(AnyQ lift-deriv (_ _ first lift second))
(join (loop first) (loop lift) (loop second))]
[(AnyQ transformation (_ _ _ _ _ locals _))
(loops locals)]
[(struct local-expansion (_ _ _ _ deriv))
(loop deriv)]
[(struct local-bind (deriv))
(loop deriv)]
[(AnyQ p:define-syntaxes (_ _ _ rhs))
(loop rhs)]
[(AnyQ p:define-values (_ _ _ rhs))
(loop rhs)]
[(AnyQ p:if (_ _ _ _ test then else))
(join (loop test) (loop then) (loop else))]
[(AnyQ p:wcm (_ _ _ key value body))
(join (loop key) (loop value) (loop body))]
[(AnyQ p:set! (_ _ _ _ rhs))
(loop rhs)]
[(AnyQ p:set!-macro (_ _ _ deriv))
(loop deriv)]
[(AnyQ p:begin (_ _ _ lderiv))
(loop lderiv)]
[(AnyQ p:begin0 (_ _ _ first lderiv))
(join (loop first) (loop lderiv))]
[(AnyQ p:#%app (_ _ _ _ lderiv))
(loop lderiv)]
[(AnyQ p:lambda (_ _ _ _ body))
(loop body)]
[(AnyQ p:case-lambda (_ _ _ rbs))
(apply join (map loop (map cdr (or rbs null))))]
[(AnyQ p:let-values (_ _ _ _ rhss body))
(join (loops rhss) (loop body))]
[(AnyQ p:letrec-values (_ _ _ _ rhss body))
(join (loops rhss) (loop body))]
[(AnyQ p:letrec-syntaxes+values (_ _ _ _ srhss _ vrhss body))
(join (loops srhss) (loops vrhss) (loop body))]
[(AnyQ p:module (_ _ _ _ body))
(loop body)]
[(AnyQ p:#%module-begin (_ _ _ pass1 pass2))
(join (loops pass1) (loops pass2))]
[(AnyQ p:rename (_ _ _ _ inner))
(loop inner)]
[(AnyQ p:synth (_ _ _ subterms))
(loops (map s:subterm-deriv
(filter s:subterm? subterms)))]
[(AnyQ lderiv (_ _ derivs))
(loops derivs)]
[(AnyQ bderiv (_ _ pass1 _ pass2))
(join (loops pass1) (loop pass2))]
[(AnyQ b:defvals (_ head))
(loop head)]
[(AnyQ b:defstx (_ deriv rhs))
(join (loop deriv) (loop rhs))]
[(AnyQ b:splice (_ head _))
(loop head)]
[(AnyQ b:expr (_ head))
(loop head)]
[(AnyQ b:begin (_ head inner))
(join (loop head) (loop inner))]
[(AnyQ mod:cons (head))
(loop head)]
[(AnyQ mod:prim (head prim))
(join (loop head) (loop prim))]
[(AnyQ mod:splice (head _))
(loop head)]
[(AnyQ mod:lift (head tail))
(join (loop head) (loop tail))]
[(AnyQ mod:lift-end (tail))
(loop tail)]
[(AnyQ mod:begin (head inner))
(join (loop head) (loop inner))]
[else zero]))
(define (loops ds)
(if (list? ds)
(apply join (map loop ds))
zero))
(loop d))
(define (find-derivs/syntax pred d)
(find-derivs (match-lambda
[(AnyQ deriv (e1 e2))
(pred e1)]
[_ #f])
(match-lambda
[(AnyQ p:module (_ _ _ _ _)) #t]
[(AnyQ lift-deriv (_ _ _ _ _)) #t]
[_ #f])
d))
)