Fix graph not considering original binds when recursing

diff --git a/tests.scm b/tests.scm
index a198dd4ac5a00e4cd71e9a88f8ae32eefbca994c..67d8b306140d6502c363fe153227ee4445c6d60e 100644 (file)
--- a/tests.scm
+++ b/tests.scm
@@ -50,6 +50,24 @@
                    bar))
            '(abs a a))
 
+(test-types (typecheck '(let ([foo 3]
+                             [bar (+ foo baz)]
+                             [baz (- bar 1)])
+                         bar))
+           'int)
+
+(test-types (typecheck '(let ([foo 3]
+                             [bar (baz foo)]
+                             [baz (lambda (x) x)])
+                         baz))
+           '(abs a a))
+
+(test-types (typecheck '(let ([foo 3]
+                             [bar (baz foo)]
+                             [baz (lambda (x) x)])
+                         bar))
+           'int)
+
 (test-prog '(+ 1 2) 3)
 (test-prog '((lambda (x) ((lambda (y) (+ x y)) 42)) 100) 142)
 

diff --git a/typecheck.scm b/typecheck.scm
index 219b010202a7f7a0127847e8372ea7e064a05efb..e96f6943767e1c5ab463398d11146d8f8ae450ce 100644 (file)
--- a/typecheck.scm
+++ b/typecheck.scm
@@ -339,12 +339,13 @@
                                        ; input: a list of binds ((x . y) (y . 3))
                                        ; returns: pair of verts, edges ((x y) . (x . y))
 (define (graph bs)
+  (define (go bs orig-bs)
     (define (find-refs prog)
       (ast-collect
        (lambda (x)
         (case (ast-type x)
                                        ; only count a reference if its a binding
-        ['var (if (assoc x bs) (list x) '())]
+          ['var (if (assoc x orig-bs) (list x) '())]
           [else '()]))
        prog))
     (if (null? bs)
@@ -358,10 +359,11 @@
 
               (rest (if (null? (cdr bs))
                         (cons '() '())
-                      (graph (cdr bs))))
+                        (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)