[uim-commit] r1642 - branches/r5rs/sigscheme

[yamaken at freedesktop.org]

Author: yamaken
Date: 2005-09-28 03:04:20 -0700 (Wed, 28 Sep 2005)
New Revision: 1642

Modified:
   branches/r5rs/sigscheme/operations.c
Log:
* sigscheme/operations.c
  - (ScmOp_map):
    * Add a FIXME comment
    * Modify comments
  - (map_singular_arg):
    * Optimize a CDR() out 
    * Rename 'ret_tail' to 'ret_last' in accordance with the name
      'last-pair' of R5RS which indicates last pair of a list
    * Rename 'args' to 'lst' since the list is not an argument list
      for a procedure but an element of the argument list.
      i.e. '(proc, lst)' is the args and 'lst' of the args is not an
      'args'
    * Add a FIXME comment
    * Modify a comment
  - (map_plural_args): Add a FIXME comment


Modified: branches/r5rs/sigscheme/operations.c
===================================================================
--- branches/r5rs/sigscheme/operations.c	2005-09-28 09:17:34 UTC (rev 1641)
+++ branches/r5rs/sigscheme/operations.c	2005-09-28 10:04:20 UTC (rev 1642)
@@ -1719,6 +1719,11 @@
     return (FUNCP(obj) || CLOSUREP(obj)) ? SCM_TRUE : SCM_FALSE;
 }
 
+/*
+ * FIXME:
+ * - Simplify with Scm_RegisterProcedureVariadic1
+ * - Replace expensive 'length' operation with CDR and NULLP
+ */
 ScmObj ScmOp_map(ScmObj args, ScmObj env)
 {
     ScmObj proc = CAR(args);
@@ -1728,37 +1733,49 @@
     if (arg_len < 2)
         SigScm_Error("map : Wrong number of arguments");
 
-    /* 1proc and 1arg case */
+    /* fast path for sinble arg case */
     if (arg_len == 2)
         return map_singular_arg(proc, CADR(args));
 
-    /* 1proc and many args case */
+    /* multiple args case */
     return map_plural_args(proc, CDR(args));
 }
 
-static ScmObj map_singular_arg(ScmObj proc, ScmObj args)
+/*
+ * FIXME: Inappropriate name 'singular'. Google "singular variable" and "single
+ * vairable".
+ */
+static ScmObj map_singular_arg(ScmObj proc, ScmObj lst)
 {
-    ScmObj ret      = SCM_FALSE;
-    ScmObj ret_tail = SCM_FALSE;
+    ScmObj ret        = SCM_FALSE;
+    ScmObj ret_last   = SCM_FALSE;
+    ScmObj mapped_elm = SCM_FALSE;
 
-    if (NULLP(args))
+    if (NULLP(lst))
         return SCM_NULL;
 
-    for (; !NULLP(args); args = CDR(args)) {
+    for (; !NULLP(lst); lst = CDR(lst)) {
         if (NFALSEP(ret)) {
-            /* lasting */
-            SET_CDR(ret_tail, CONS(Scm_call(proc, LIST_1(CAR(args))), SCM_NULL));
-            ret_tail = CDR(ret_tail);
+            /* subsequent */
+            mapped_elm = CONS(Scm_call(proc, LIST_1(CAR(lst))), SCM_NULL);
+            SET_CDR(ret_last, mapped_elm);
+            ret_last = mapped_elm;
         } else {
             /* first */
-            ret = CONS(Scm_call(proc, LIST_1(CAR(args))), SCM_NULL);
-            ret_tail = ret;
+            ret = CONS(Scm_call(proc, LIST_1(CAR(lst))), SCM_NULL);
+            ret_last = ret;
         }
     }
 
     return ret;
 }
 
+/*
+ * FIXME:
+ * - Inappropriate name 'plural'. Google "plural variable" and "multiple
+ *   vairable".
+ * - Simplify and make names appropriate as like as map_singular_arg()
+ */
 static ScmObj map_plural_args(ScmObj proc, ScmObj args)
 {
     ScmObj map_arg      = SCM_FALSE;