[WWcvs] pg: Fixed a problem where intervals minus sets containing more than one point were not being handled properly.

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

Log Message:
-----------
Fixed a problem where intervals minus sets containing more than one
point were not being handled properly.

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

Revision Data
-------------
Index: Set.pm
===================================================================
RCS file: /webwork/cvs/system/pg/lib/Value/Set.pm,v
retrieving revision 1.20
retrieving revision 1.21
diff -Llib/Value/Set.pm -Llib/Value/Set.pm -u -r1.20 -r1.21
--- lib/Value/Set.pm
+++ lib/Value/Set.pm
@@ -138,7 +138,7 @@
     } elsif ($x < $b) {
       my $context = $self->context;
       push(@union,$context->Package("Interval")->make($context,$I->{open},$a,$x,')'));
-      $I->{open} = '('; $I->{data}[0] = $x;
+      $I->{open} = '('; $I->{data}[0] = $a = $x;
     } else {
       $I->{close} = ')' if ($x == $b);
       last;