Refactoring n-ary functions to use a single helper.

* lib.c (nary_op): New function.
(plusv, mulv, logandv, logiorv): Use nary_op.

* lib.h (nary_op): Declared.

3 files changed, 23 insertions, 20 deletions

diff --git a/ChangeLog b/ChangeLog
index ec5a5d2d..99614ffb 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,12 @@
+2015-06-24  Kaz Kylheku  <kaz@kylheku.com>
+
+	Refactoring n-ary functions to use a single helper.
+
+	* lib.c (nary_op): New function.
+	(plusv, mulv, logandv, logiorv): Use nary_op.
+
+	* lib.h (nary_op): Declared.
+
 2015-06-23  Kaz Kylheku  <kaz@kylheku.com>
 
 	Hash subset testing.
diff --git a/lib.c b/lib.c
index 0e8a15e1..6e9e2d8e 100644
--- a/lib.c
+++ b/lib.c
@@ -2074,13 +2074,18 @@ val numberp(val num)
   }
 }
 
+val nary_op(val (*cfunc)(val, val), val args, val emptyval)
+{
+  if (!args)
+    return emptyval;
+  else if (!cdr(args))
+    return car(args);
+  return reduce_left(func_n2(cfunc), cdr(args), car(args), nil);
+}
+
 val plusv(val nlist)
 {
-  if (!nlist)
-    return num(0);
-  else if (!cdr(nlist))
-    return car(nlist);
-  return reduce_left(func_n2(plus), cdr(nlist), car(nlist), nil);
+  return nary_op(plus, nlist, zero);
 }
 
 val minusv(val minuend, val nlist)
@@ -2092,29 +2097,17 @@ val minusv(val minuend, val nlist)
 
 val mulv(val nlist)
 {
-  if (!nlist)
-    return one;
-  else if (!cdr(nlist))
-    return car(nlist);
-  return reduce_left(func_n2(mul), cdr(nlist), car(nlist), nil);
+  return nary_op(mul, nlist, one);
 }
 
 val logandv(val nlist)
 {
-  if (!nlist)
-    return negone;
-  else if (!cdr(nlist))
-    return car(nlist);
-  return reduce_left(func_n2(logand), cdr(nlist), car(nlist), nil);
+  return nary_op(logand, nlist, negone);
 }
 
 val logiorv(val nlist)
 {
-  if (!nlist)
-    return zero;
-  else if (!cdr(nlist))
-    return car(nlist);
-  return reduce_left(func_n2(logior), cdr(nlist), car(nlist), nil);
+  return nary_op(logior, nlist, zero);
 }
 
 val gtv(val first, val rest)
diff --git a/lib.h b/lib.h
index 66cc89da..cd78205e 100644
--- a/lib.h
+++ b/lib.h
@@ -536,6 +536,7 @@ val bignump(val num);
 val floatp(val num);
 val integerp(val num);
 val numberp(val num);
+val nary_op(val (*cfunc)(val, val), val args, val emptyval);
 val plus(val anum, val bnum);
 val plusv(val nlist);
 val minus(val anum, val bnum);