X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2Fconstant.pm;h=5d3dd91b46f94f01999fd9eed46aab737dfe0ed8;hb=4499d6b9d14594604210bc28005c5e4ab2e49947;hp=464e20cd91d0ec64543da8a63c38ffcc6f08ec2d;hpb=a3cb178b0bad32fa8be934503d051b96a3cb1fea;p=p5sagit%2Fp5-mst-13.2.git

diff --git a/lib/constant.pm b/lib/constant.pm
index 464e20c..5d3dd91 100644
--- a/lib/constant.pm
+++ b/lib/constant.pm
@@ -20,6 +20,18 @@ constant - Perl pragma to declare constants
 
     print "This line does nothing"		unless DEBUGGING;
 
+    # references can be declared constant
+    use constant CHASH		=> { foo => 42 };
+    use constant CARRAY		=> [ 1,2,3,4 ];
+    use constant CPSEUDOHASH	=> [ { foo => 1}, 42 ];
+    use constant CCODE		=> sub { "bite $_[0]\n" };
+
+    print CHASH->{foo};
+    print CARRAY->[$i];
+    print CPSEUDOHASH->{foo};
+    print CCODE->("me");
+    print CHASH->[10];				# compile-time error
+
 =head1 DESCRIPTION
 
 This will declare a symbol to be a constant with the given scalar
@@ -86,6 +98,8 @@ constants at compile time, allowing for way cool stuff like this.
     print   E2BIG, "\n";	# something like "Arg list too long"
     print 0+E2BIG, "\n";	# "7"
 
+Errors in dereferencing constant references are trapped at compile-time.
+
 =head1 TECHNICAL NOTE
 
 In the current implementation, scalar constants are actually