X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FMooseX%2FTypes%2FTypeDecorator.pm;h=fdbaf9fcabec4fad88dbcb2f6e061f39a7f50434;hb=0d07f026067efc017e030c8c9a8e0faad6f55166;hp=12c7f4803b3bacd785f2913b07d38b3d41203974;hpb=442e42ba3e90b69452a0c8c2a78cd55d2304262a;p=gitmo%2FMooseX-Types.git

diff --git a/lib/MooseX/Types/TypeDecorator.pm b/lib/MooseX/Types/TypeDecorator.pm
index 12c7f48..fdbaf9f 100644
--- a/lib/MooseX/Types/TypeDecorator.pm
+++ b/lib/MooseX/Types/TypeDecorator.pm
@@ -24,10 +24,18 @@ use overload(
         ## is needed for syntax compatibility.  Maybe someday we'll all just do
         ## Or[Str,Str,Int]
 
-	my @tc = map {
-	    blessed $_ ? $_ :
-	      Moose::Util::TypeConstraints::find_or_parse_type_constraint($_)
-	} @_;
+        my @args = @_[0,1]; ## arg 3 is special,  see the overload docs.
+        my @tc = grep {blessed $_} map {
+            blessed $_ ? $_ :
+            Moose::Util::TypeConstraints::find_or_parse_type_constraint($_)
+              || croak "$_ is not a type constraint"
+        } @args;
+
+        ( scalar @tc == scalar @args)
+            || croak "one of your type constraints is bad.  Passed: ". join(', ', @args) ." Got: ". join(', ', @tc);
+
+        ( scalar @tc >= 2 )
+            || croak "You must pass in at least 2 type names to make a union";
 
         my $union = Moose::Meta::TypeConstraint::Union->new(type_constraints=>\@tc);
         return Moose::Util::TypeConstraints::register_type_constraint($union);