[WWcvs] pg: Avoid error when a CODE reference is checked to see if it is a Value

[dpvc v. a. <we...@ma...>]

Log Message:
-----------
Avoid error when a CODE reference is checked to see if it is a Value object.

Modified Files:
--------------
    pg/lib:
        Value.pm

Revision Data
-------------
Index: Value.pm
===================================================================
RCS file: /webwork/cvs/system/pg/lib/Value.pm,v
retrieving revision 1.50
retrieving revision 1.51
diff -Llib/Value.pm -Llib/Value.pm -u -r1.50 -r1.51
--- lib/Value.pm
+++ lib/Value.pm
@@ -136,10 +136,10 @@
   return class($v) eq 'Formula' ||
          (ref($v) && ref($v) ne 'ARRAY' && $v->{isFormula});
 }
-sub isValue   {
+sub isValue {
   my $v = shift;
   return (ref($v) || $v) =~ m/^Value::/ ||
-         (ref($v) && ref($v) ne 'ARRAY' && $v->{isValue});
+         (ref($v) && ref($v) ne 'ARRAY' && ref($v) ne 'CODE' && $v->{isValue});
 }
 
 sub isNumber {