Patch

[Dirk Herrmann <dirk at ida dot ing dot tu-bs dot de>]

Hi.

When looking at alist.c, I realized some places that could be
improved.  I have not gone through all of it, though.  I intend to look at
guile in small units, as my time allows, so please forgive that I send
patches in small units.


===================================================================
RCS file: /cvs/guile/guile/guile-core/libguile/alist.c,v
retrieving revision 1.15
diff -u -p -r1.15 alist.c
--- alist.c     2000/01/05 19:25:35     1.15
+++ alist.c     2000/01/06 13:09:47
@@ -147,12 +147,14 @@ predicate is in use), then @code{#f} is 
 return the entire alist entry found (i.e. both the key and the value).")
 #define FUNC_NAME s_scm_assq
 {
-  SCM tmp;
-  for(;SCM_NIMP(alist);alist = SCM_CDR(alist)) {
-    SCM_VALIDATE_ALISTCELL_COPYSCM (2,alist,tmp);
-    if (SCM_CAR(tmp)==key) return tmp;
-  }
-  SCM_VALIDATE_NULL (2,alist);
+  for (; SCM_CONSP(alist); alist = SCM_CDR(alist)) 
+    {
+      SCM tmp = SCM_CAR(alist);
+      SCM_VALIDATE_CONS(2, tmp);
+      if (SCM_CAR(tmp) == key) 
+       return tmp;
+    }
+  SCM_VALIDATE_NULL(2, alist);
   return SCM_BOOL_F;
 }
 #undef FUNC_NAME
@@ -163,17 +165,14 @@ SCM_DEFINE (scm_assv, "assv", 2, 0, 0,
 "Behaves like @code{assq} but uses @code{eqv?} for key comparison.")
 #define FUNC_NAME s_scm_assv
 {
-  SCM tmp;
-  for(;SCM_NIMP(alist);alist = SCM_CDR(alist)) {
-    SCM_ASRTGO(SCM_CONSP(alist), badlst);
-    tmp = SCM_CAR(alist);
-    SCM_ASRTGO(SCM_CONSP(tmp), badlst);
-    if SCM_NFALSEP(scm_eqv_p(SCM_CAR(tmp), key)) return tmp;
-  }
-# ifndef SCM_RECKLESS
-  if (!(SCM_NULLP(alist)))
-    badlst: SCM_WTA(2,alist);
-# endif
+  for(; SCM_CONSP(alist); alist = SCM_CDR(alist)) 
+    {
+      SCM tmp = SCM_CAR(alist);
+      SCM_VALIDATE_CONS(2, tmp);
+      if SCM_NFALSEP(scm_eqv_p(SCM_CAR(tmp), key))
+       return tmp;
+    }
+  SCM_VALIDATE_NULL(2, alist);
   return SCM_BOOL_F;
 }
 #undef FUNC_NAME
@@ -184,12 +183,14 @@ SCM_DEFINE (scm_assoc, "assoc", 2, 0, 0,
 "Behaves like @code{assq} but uses @code{equal?} for key comparison.")
 #define FUNC_NAME s_scm_assoc
 {
-  SCM tmp;
-  for(;SCM_NIMP(alist);alist = SCM_CDR(alist)) {
-    SCM_VALIDATE_ALISTCELL_COPYSCM (2,alist,tmp);
-    if SCM_NFALSEP(scm_equal_p(SCM_CAR(tmp), key)) return tmp;
-  }
-  SCM_VALIDATE_NULL (2,alist);
+  for(; SCM_CONSP(alist); alist = SCM_CDR(alist)) 
+    {
+      SCM tmp = SCM_CAR(alist);
+      SCM_VALIDATE_CONS(2, tmp);
+      if SCM_NFALSEP(scm_equal_p(SCM_CAR(tmp), key)) 
+       return tmp;
+    }
+  SCM_VALIDATE_NULL(2, alist);
   return SCM_BOOL_F;
 }
 #undef FUNC_NAME


* The scope of the tmp variables is minimized.
* The tmp variables are initialized at the same moment they are declared.
* The strange SCM_NIMP tests are replaced by SCM_CONSP tests that more closely
  reflect the intended semantics.  However, we don't get a performance penalty
  here, because the SCM_CONSP test was performed by the ALISTCELL test anyway.
* The extremely ugly use of ASRTGO macros was removed:  The calls to ASRTGO
  were not encapsulated by "#ifndef SCM_RECKLESS", but got a label parameter
  that only exists when SCM_RECKLESS is not defined.  This works, because
  ASRTGO itself is defined in a way that it only makes use of the label
  parameter if SCM_RECKLESS is not defined (shudder!).  Does guile make at all
  use of the possibility to define SCM_RECKLESS?
* Codesize is likely to be reduced, since instead of two calls to SCM_ASSERT
  performed by the ALISTCELL test we now only get one test.


Best regards
Dirk Herrmann