* lib.c (min2, max2): Semantics tweak. If the numbers are equal,

favor the left one.

* txr.1: Documented min and max.

3 files changed, 34 insertions, 2 deletions

diff --git a/ChangeLog b/ChangeLog
index 78c88285..644b73df 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,12 @@
 2012-03-29  Kaz Kylheku  <kaz@kylheku.com>
 
+	* lib.c (min2, max2): Semantics tweak. If the numbers are equal,
+	favor the left one.
+
+	* txr.1: Documented min and max.
+
+2012-03-29  Kaz Kylheku  <kaz@kylheku.com>
+
 	* arith.c (numeq): New function.
 	(exptmod): Bugfix: was no normalizing the bignum, ouch.
 	Also was reporting "non-integral operands" for other
diff --git a/lib.c b/lib.c
index d354ce6e..eb756086 100644
--- a/lib.c
+++ b/lib.c
@@ -1285,12 +1285,12 @@ val numeqv(val first, val rest)
 
 val max2(val anum, val bnum)
 {
-  return if3(gt(anum, bnum), anum, bnum);
+  return if3(ge(anum, bnum), anum, bnum);
 }
 
 val min2(val anum, val bnum)
 {
-  return if3(lt(anum, bnum), anum, bnum);
+  return if3(le(anum, bnum), anum, bnum);
 }
 
 val maxv(val first, val rest)
diff --git a/txr.1 b/txr.1
index d104df86..13724a41 100644
--- a/txr.1
+++ b/txr.1
@@ -7087,6 +7087,31 @@ character will convert to integer.
 
 .SS Functions max and min
 
+.TP
+Syntax:
+
+  (max <number> <number>*)
+  (min <number> <number>*)
+
+.TP
+Description:
+
+The max and min functions determine and return the highest or lowest
+value from among their arguments.
+
+The arguments must be numbers or characters.
+
+If only a single argument is given, that value is returned.
+
+If two arguments are given, then (max a b) is equivalent to (if (>= a b) a b),
+and (min a b) is equivalent to (if (<= a b) a b). If the operands do not
+have the same type, then one of them is converted to the type of the other;
+however, the original unconverted values are returned. For instance
+(max 4 3.0) yields the integer 4, not 4.0.
+
+If three or more arguments are given, max and min are left-associative.
+Thus (max a b c) is (max (max a b) c).
+
 .SS Functions search-regex and match-regex
 
 .SS Function regsub