X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2Fvars.pm;h=bde0b2a0e8c2274a44d07e7537c9b3739ee4b9ff;hb=8c99d73ee7ce90de2561496f683f3850d1269e1d;hp=e007baa7b9e798c1ad96e690d01bb324684c7751;hpb=7a2e2cd6e4407ff4fe23355f0373307425305867;p=p5sagit%2Fp5-mst-13.2.git

diff --git a/lib/vars.pm b/lib/vars.pm
index e007baa..bde0b2a 100644
--- a/lib/vars.pm
+++ b/lib/vars.pm
@@ -1,8 +1,51 @@
 package vars;
 
+require 5.002;
+
+# The following require can't be removed during maintenance
+# releases, sadly, because of the risk of buggy code that does
+# require Carp; Carp::croak "..."; without brackets dying
+# if Carp hasn't been loaded in earlier compile time. :-(
+# We'll let those bugs get found on the development track.
+require Carp if $] < 5.00450;
+use warnings::register();
+
+sub import {
+    my $callpack = caller;
+    my ($pack, @imports, $sym, $ch) = @_;
+    foreach $sym (@imports) {
+        ($ch, $sym) = unpack('a1a*', $sym);
+	if ($sym =~ tr/A-Za-z_0-9//c) {
+	    # time for a more-detailed check-up
+	    if ($sym =~ /::/) {
+		require Carp;
+		Carp::croak("Can't declare another package's variables");
+	    } elsif ($sym =~ /^\w+[[{].*[]}]$/) {
+		require Carp;
+		Carp::croak("Can't declare individual elements of hash or array");
+	    } elsif (warnings::enabled() and length($sym) == 1 and $sym !~ tr/a-zA-Z//) {
+		warnings::warn("No need to declare built-in vars");
+	    }
+	}
+        *{"${callpack}::$sym"} =
+          (  $ch eq "\$" ? \$   {"${callpack}::$sym"}
+           : $ch eq "\@" ? \@   {"${callpack}::$sym"}
+           : $ch eq "\%" ? \%   {"${callpack}::$sym"}
+           : $ch eq "\*" ? \*   {"${callpack}::$sym"}
+           : $ch eq "\&" ? \&   {"${callpack}::$sym"}
+           : do {
+		require Carp;
+		Carp::croak("'$ch$sym' is not a valid variable name");
+	     });
+    }
+};
+
+1;
+__END__
+
 =head1 NAME
 
-vars - Perl pragma to predeclare global variable names
+vars - Perl pragma to predeclare global variable names (obsolete)
 
 =head1 SYNOPSIS
 
@@ -10,6 +53,10 @@ vars - Perl pragma to predeclare global variable names
 
 =head1 DESCRIPTION
 
+NOTE: The functionality provided by this pragma has been superseded
+by C<our> declarations, available in Perl v5.6.0 or later.  See
+L<perlfunc/our>.
+
 This will predeclare all the variables whose names are 
 in the list, allowing you to use them under "use strict", and
 disabling any typo warnings.
@@ -27,27 +74,6 @@ outside of the package), it can act as an acceptable substitute by
 pre-declaring global symbols, ensuring their availability to the
 later-loaded routines.
 
-See L<perlmod/Pragmatic Modules>.
+See L<perlmodlib/Pragmatic Modules>.
 
 =cut
-
-require 5.002;
-use Carp;
-
-sub import {
-    my $callpack = caller;
-    my ($pack, @imports, $sym, $ch) = @_;
-    foreach $sym (@imports) {
-	croak "Can't declare another package's variables" if $sym =~ /::/;
-        ($ch, $sym) = unpack('a1a*', $sym);
-        *{"${callpack}::$sym"} =
-          (  $ch eq "\$" ? \$   {"${callpack}::$sym"}
-           : $ch eq "\@" ? \@   {"${callpack}::$sym"}
-           : $ch eq "\%" ? \%   {"${callpack}::$sym"}
-           : $ch eq "\*" ? \*   {"${callpack}::$sym"}
-           : $ch eq "\&" ? \&   {"${callpack}::$sym"}
-           : croak "'$ch$sym' is not a valid variable name\n");
-    }
-};
-
-1;