(inner (lambda-body x)))]
['if (append (f x)
(flat-map inner (cdr x)))]
+ ['closure (flat-map inner (caddr x))]
[else (f x)]))
(define (ast-find p x)
[else (p x)]))
(define (let-bindings e)
- (define (pattern-match x body)
- (if (eqv? (ast-type x) 'var)
- (list (cons x body))
- (let* ([constructor (car x)]
+ (define (pattern-match binding body)
+ (if (eqv? (ast-type binding) 'var)
+ (list (cons binding body))
+ (let* ([constructor (car binding)]
[destructor (lambda (i) (dtor-name constructor i))])
(flat-map (lambda (y i)
- (pattern-match y (list (destructor i) body)))
- (cdr x)
- (range 0 (length (cdr x)))))))
+ (pattern-match y `((,(destructor i) ,@body))))
+ (cdr binding)
+ (range 0 (length (cdr binding)))))))
(flat-map (lambda (x) (pattern-match (car x) (cdr x))) (cadr e)))
(define let-body cddr)
program))
(define (program-body program)
+ ; hack to have multi-expression bodies
`(let ()
,@(filter (lambda (x) (eqv? (statement-type x) 'expr))
program)))
+
+ ; (A ((foo (Int Bool))
+ ; (bar (Bool)))
+
+(define data-layout cdr)
+
; gets both constructors and destructors
; (data A (foo Int Bool)
; (bar Bool))
; |
; v
- ; (foo . (abs Int (abs Bool A)))
- ; (foo~0 . (abs A Int)
- ; (foo~1 . (abs A Bool)
- ; (bar . (abs Bool A)
- ; (bar~0 . (abs A Bool)
+ ; (foo . (constructor . (abs Int (abs Bool A))))
+ ; (foo~0 . (0 . (abs A Int)))
+ ; (foo~1 . (1 . (abs A Bool)))
+ ; (bar . (constructor . (abs Bool A)))
+ ; (bar~0 . (0 . (abs A Bool)))
-(define (data-tors data-def)
+(define (data-tors data-layout)
(define (constructor-type t products)
(fold-right (lambda (x acc) `(abs ,x ,acc)) t products))
(define (destructor ctor-name prod-type part-type index)
(let ([name (dtor-name ctor-name index)])
- (cons name `(abs ,prod-type ,part-type))))
+ (cons name (cons index `(abs ,prod-type ,part-type)))))
- (let ([type-name (cadr data-def)]
- [ctors (cddr data-def)])
+ (let ([type-name (car data-layout)]
+ [ctors (cdr data-layout)])
(fold-right
(lambda (ctor acc)
(let* ([ctor-name (car ctor)]
[products (cdr ctor)]
- [maker (cons ctor-name (constructor-type type-name products))]
+ [maker (cons ctor-name (cons 'constructor (constructor-type type-name products)))]
[dtors (map (lambda (t i) (destructor ctor-name type-name t i))
products
(cons maker (append dtors acc))))
'()
- ctrs)))
+ ctors)))
+
+ ; creates a type environment for a given adt definition
+(define (data-tors-env data-layout)
+ (map (lambda (x) (cons (car x) (cddr x))) (data-tors data-layout)))
(define (dtor-name ctor-name index)
(string->symbol
(define lambda-args cadr)
(define lambda-body caddr)
+(define (references prog)
+ (ast-collect
+ (lambda (x)
+ (case (ast-type x)
+ ['var (list x)]
+ [else '()]))
+ prog))
+
+(define (graph bs)
+ (define (go bs orig-bs)
+ (if (null? bs)
+ '(() . ())
+ (let* [(bind (car bs))
+
+ (vert (car bind))
+ (refs (filter ; only count a reference if its a binding
+ (lambda (x) (assoc x orig-bs))
+ (references (cdr bind))))
+ (edges (map (lambda (x) (cons vert x))
+ refs))
+
+ (rest (if (null? (cdr bs))
+ (cons '() '())
+ (go (cdr bs) orig-bs)))
+ (total-verts (cons vert (car rest)))
+ (total-edges (append edges (cdr rest)))]
+ (cons total-verts total-edges))))
+ (go bs bs))
+
+(define (successors graph v)
+ (define (go v E)
+ (if (null? E)
+ '()
+ (if (eqv? v (caar E))
+ (cons (cdar E) (go v (cdr E)))
+ (go v (cdr E)))))
+ (go v (cdr graph)))
+
+ ; takes in a graph (pair of vertices, edges)
+ ; returns a list of strongly connected components
+
+ ; ((x y w) . ((x . y) (x . w) (w . x))
+
+ ; =>
+ ; .->x->y
+ ; | |
+ ; | v
+ ; .--w
+
+ ; ((x w) (y))
+
+ ; this uses tarjan's algorithm, to get reverse
+ ; topological sorting for free
+(define (sccs graph)
+
+ (let* ([indices (make-hash-table)]
+ [lowlinks (make-hash-table)]
+ [on-stack (make-hash-table)]
+ [current 0]
+ [stack '()]
+ [result '()])
+
+ (define (index v)
+ (get-hash-table indices v #f))
+ (define (lowlink v)
+ (get-hash-table lowlinks v #f))
+
+ (letrec
+ ([strong-connect
+ (lambda (v)
+ (begin
+ (put-hash-table! indices v current)
+ (put-hash-table! lowlinks v current)
+ (set! current (+ current 1))
+ (push! stack v)
+ (put-hash-table! on-stack v #t)
+
+ (for-each
+ (lambda (w)
+ (if (not (hashtable-contains? indices w))
+ ; successor w has not been visited, recurse
+ (begin
+ (strong-connect w)
+ (put-hash-table! lowlinks
+ v
+ (min (lowlink v) (lowlink w))))
+ ; successor w has been visited
+ (when (get-hash-table on-stack w #f)
+ (put-hash-table! lowlinks v (min (lowlink v) (index w))))))
+ (successors graph v))
+
+ (when (= (index v) (lowlink v))
+ (let ([scc
+ (let new-scc ()
+ (let ([w (pop! stack)])
+ (put-hash-table! on-stack w #f)
+ (if (eqv? w v)
+ (list w)
+ (cons w (new-scc)))))])
+ (set! result (cons scc result))))))])
+ (for-each
+ (lambda (v)
+ (when (not (hashtable-contains? indices v)) ; v.index == -1
+ (strong-connect v)))
+ (car graph)))
+ result))
+
+
; utils
+
(define (range s n)
(if (= 0 n) '()
(append (range s (- n 1))
projects / scheme.git / blobdiff