enable R5RS map' & for-each' (i.e., mmap' and mfor-each') inlining

original commit: 4b1f74671429f6d8955c6afa98569821fec9e8c7

collects/racket/mpair.rkt

@@ -1,6 +1,7 @@
 #lang scheme/base
 
-(require (for-syntax scheme/base))
+(require (for-syntax scheme/base)
+         "performance-hint.rkt")
 
 (provide mmap
          mfor-each
@@ -23,6 +24,7 @@
          list->mlist
          mlistof)
 
+(begin-encourage-inline
  (define mmap
    (case-lambda
     [(f l) (let loop ([l l])
@@ -56,7 +58,7 @@
                   (cond
                    [(null? l) (void)]
                    [else (apply f (mcar l) (map mcar ls))
-                        (loop (mcdr l) (map mcdr ls))]))]))
+                         (loop (mcdr l) (map mcdr ls))]))])))
 
 (define (list->mlist l)
   (cond