Generalize type of curry to functions of arity 3+.

original commit: 088006413f3ec10dcf188b7b21668a89409f27a5

collects/tests/typed-racket/succeed/curry.rkt

@@ -0,0 +1,25 @@
+#lang typed/racket
+
+(: f2 (Boolean Integer Integer -> Integer))
+(define (f2 add? i1 i2)
+  (if add?
+      (+ i1 i2)
+      (- i1 i2)))
+
+(: f3 (Boolean Integer Integer Integer -> Integer))
+(define (f3 add? i1 i2 i3)
+  (if add?
+      (+ i1 i2 i3)
+      (- i1 i2 i3)))
+
+(define f1a (curry f2 #t))
+(define f1b (curry f3 #t))
+(define f2a (curry f2))
+(define f2b (curry f3))
+
+(f2 #t 2 3)
+(f2 #f 2 1)
+(f1a 10 20)
+(f1b 10 20 30)
+((f2a #t) 10 20)
+((f2b #t) 10 20 30)

collects/typed-racket/base-env/base-env.rkt

@@ -1772,9 +1772,11 @@
 
 
 ;; probably the most useful cases
-[curry (-poly (a b c)
-              (cl->* ((a b . -> . c) a . -> . (b . -> . c))
-                     ((a b . -> . c) . -> . (a . -> . (b . -> . c)))))]
+;; doesn't cover cases where we pass multiple of the function's arguments to curry,
+;; also doesn't express that the returned function is itself curried
+[curry (-polydots (a c b)
+                  (cl->* ((->... (list a) (b b) c) a . -> . (->... '() (b b) c))
+                         ((->... (list a) (b b) c) . -> . (a . -> . (->... '() (b b) c)))))]
 ;; mutable pairs
 [mcons (-poly (a b) (-> a b (-mpair a b)))]
 [mcar (-poly (a b)