[WWcvs] pg: Make formulas that produce lists get default open and close parens,

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

Log Message:
-----------
Make formulas that produce lists get default open and close parens,
and have them retained in Formula() results.

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

Revision Data
-------------
Index: Parser.pm
===================================================================
RCS file: /webwork/cvs/system/pg/lib/Parser.pm,v
retrieving revision 1.28
retrieving revision 1.29
diff -Llib/Parser.pm -Llib/Parser.pm -u -r1.28 -r1.29
--- lib/Parser.pm
+++ lib/Parser.pm
@@ -26,8 +26,9 @@
   my $context = Parser::Context->current;
   my $class = $context->{parser}{Formula};
   my $string = shift;
-  $string = Value::List->new($string,@_)
-    if scalar(@_) > 0 || ref($string) eq 'ARRAY';
+  $string = Value::List->new($string,@_) if scalar(@_) > 0;
+  $string = Value::List->new($string)->with(open=>'[',close=>']')
+    if ref($string) eq 'ARRAY';
   my $math = bless {
     string => undef,
     tokens => [], tree => undef, 
Index: Formula.pm
===================================================================
RCS file: /webwork/cvs/system/pg/lib/Value/Formula.pm,v
retrieving revision 1.33
retrieving revision 1.34
diff -Llib/Value/Formula.pm -Llib/Value/Formula.pm -u -r1.33 -r1.34
--- lib/Value/Formula.pm
+++ lib/Value/Formula.pm
@@ -34,9 +34,14 @@
          '""' => sub {shift->stringify(@_)};
 
 #
-#  Call Parser to make the new item
+#  Call Parser to make the new item, copying important
+#    fields from the tree.
 #
-sub new {shift; $pkg->SUPER::new(@_)}
+sub new {
+  shift; my $self = $pkg->SUPER::new(@_);
+  foreach my $id ('open','close') {$self->{$id} = $self->{tree}{$id}}
+  return $self;
+}
 
 #
 #  Create the new parser with no string
@@ -66,6 +71,8 @@
 sub isZero {(shift)->{tree}{isZero}}
 sub isOne {(shift)->{tree}{isOne}}
 
+sub isSetOfReals {(shift)->type =~ m/Interval|Set|Union/}
+
 ############################################
 #
 #  Create a BOP from two operands
@@ -97,7 +104,7 @@
   $l = $parser->{Value}->new($formula,$l) unless ref($l) =~ m/^Parser::/;
   $r = $parser->{Value}->new($formula,$r) unless ref($r) =~ m/^Parser::/;
   $bop = 'U' if $bop eq '+' &&
-    ($l->type =~ m/Interval|Union|Set/ || $r->type =~ m/Interval|Union|Set/);
+    ($l->type =~ m/Interval|Set|Union/ || $r->type =~ m/Interval|Set|Union/);
   $formula->{tree} = $parser->{BOP}->new($formula,$bop,$l,$r);
   $formula->{variables} = $formula->{tree}->getVariables;
   return $formula->eval if scalar(%{$formula->{variables}}) == 0;