Use the correct field numbers in substructs.

Maintain table of struct accessors/mutators.

collects/tests/typed-scheme/succeed/test-child-field.rkt

@@ -0,0 +1,10 @@
+#lang typed/racket
+
+(define-struct:  x ([a : Any]))
+(define-struct: (A) (y x) ([b : A]))
+
+(: f : (y Any) -> String)
+(define (f v)
+  (if (string? (y-b v))
+      (y-b v)
+      "foo"))

collects/typed-scheme/rep/type-rep.rkt

@@ -18,8 +18,7 @@
           (not (ValuesDots? e))
           (not (Result? e)))))
 
-(define Type/c
+(define Type/c (flat-named-contract 'Type Type/c?))
-  (flat-named-contract 'Type Type/c?))
 
 ;; Name = Symbol
 

collects/typed-scheme/typecheck/tc-structs.rkt

@@ -3,7 +3,7 @@
 (require "../utils/utils.rkt" 
 	 (except-in (rep type-rep free-variance) Dotted)
          (private parse-type)
-	 (types convenience utils union resolve abbrev substitute)
+	 (types convenience utils union resolve abbrev substitute type-table)
 	 (env global-env type-env-structs type-name-env tvar-env)
 	 (utils tc-utils)
          "def-binding.rkt"
@@ -142,10 +142,10 @@
                                  (or (eq? variance Constant)
                                      (eq? variance Covariant))))
                              #t)))
+  (define parent-count (- (length external-fld-types) (length external-fld-types/no-parent)))
   ;; the list of names w/ types
   (define bindings
-    (append 
+    (list* 
-     (list 
      (cons struct-type-id
            (make-StructType sty))
      (cons (or maker* maker)
@@ -153,15 +153,20 @@
      (cons (or pred* pred)
            (make-pred-ty (if (not covariant?)
                              (make-StructTop sty)
-                              (pred-wrapper name)))))
+                             (pred-wrapper name))))
-     (for/list ([g (in-list getters)] [t (in-list external-fld-types/no-parent)] [i (in-naturals)])
+     (append
-       (let ([func (if setters? 
+      (for/list ([g (in-list getters)] [t (in-list external-fld-types/no-parent)] [i (in-naturals parent-count)])
+        (let* ([path (make-StructPE name i)]
+               [func (if setters? 
                          (->* (list name) t)
-		       (->acc (list name) t (list (make-StructPE name i))))])
+                         (->acc (list name) t (list path)))])
+          (add-struct-fn! g path #f)
           (cons g (wrapper func))))
       (if setters?
-         (map (lambda (g t) (cons g (wrapper (->* (list name t) -Void)))) setters external-fld-types/no-parent)
+          (for/list ([g (in-list setters)] [t (in-list external-fld-types/no-parent)] [i (in-naturals parent-count)])
-         null)))
+            (add-struct-fn! g (make-StructPE name i) #t)        
+            (cons g (wrapper (->* (list name t) -Void))))
+          null))))
   (register-type-name nm (wrapper sty))
   (cons
    (make-def-struct-stx-binding nm si)

collects/typed-scheme/types/type-table.rkt

@@ -1,6 +1,7 @@
 #lang scheme/base
 
-(require unstable/debug "../utils/utils.rkt" (rep type-rep) (only-in (types abbrev utils) tc-results?) (utils tc-utils) scheme/contract)
+(require unstable/debug scheme/contract "../utils/utils.rkt" syntax/id-table racket/dict racket/match
+         (rep type-rep object-rep) (only-in (types abbrev utils) tc-results?) (utils tc-utils))
 
 (define table (make-hasheq))
 
@@ -12,6 +13,21 @@
 
 (define (type-of e) (hash-ref table e (lambda () (int-err (format "no type for ~a" (syntax->datum e))))))
 
+(define struct-fn-table (make-free-id-table))
+
+(define (add-struct-fn! id pe mut?) (dict-set! struct-fn-table id (list pe mut?)))
+
+(define-values (struct-accessor? struct-mutator?) 
+  (let ()
+    (define ((mk mut?) id)
+      (cond [(dict-ref struct-fn-table id #f)
+              => (match-lambda [(list pe #f) pe] [_ #f])]
+            [else #f]))
+    (values (mk #f) (mk #t))))
+
 (p/c [add-typeof-expr (syntax? tc-results? . -> . any/c)]
      [type-of (syntax? . -> . tc-results?)]
-     [reset-type-table (-> any/c)])
+     [reset-type-table (-> any/c)]
+     [add-struct-fn! (identifier? StructPE? boolean? . -> . any/c)]
+     [struct-accessor? (identifier? . -> . (or/c #f StructPE?))]
+     [struct-mutator? (identifier? . -> . (or/c #f StructPE?))])