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-rw-r--r--lib/strict.pm68
1 files changed, 68 insertions, 0 deletions
diff --git a/lib/strict.pm b/lib/strict.pm
index adaf47c720..d35c6c105c 100644
--- a/lib/strict.pm
+++ b/lib/strict.pm
@@ -1,5 +1,73 @@
package strict;
+=head1 NAME
+
+strict - Perl pragma to restrict unsafe constructs
+
+=head1 SYNOPSIS
+
+ use strict;
+
+ use strict "vars";
+ use strict "refs";
+ use strict "subs";
+
+ use strict;
+ no strict "vars";
+
+=head1 DESCRIPTION
+
+If no import list is supplied, all possible restrictions are assumed.
+(This is the safest mode to operate in, but is sometimes too strict for
+casual programming.) Currently, there are three possible things to be
+strict about: "subs", "vars", and "refs".
+
+=over 6
+
+=item C<strict refs>
+
+This generates a runtime error if you
+use symbolic references (see L<perlref>).
+
+ use strict 'refs';
+ $ref = \$foo;
+ print $$ref; # ok
+ $ref = "foo";
+ print $$ref; # runtime error; normally ok
+
+=item C<strict vars>
+
+This generates a compile-time error if you access a variable that wasn't
+localized via C<my()> or wasn't fully qualified. Because this is to avoid
+variable suicide problems and subtle dynamic scoping issues, a merely
+local() variable isn't good enough. See L<perlfunc/my> and
+L<perlfunc/local>.
+
+ use strict 'vars';
+ $X::foo = 1; # ok, fully qualified
+ my $foo = 10; # ok, my() var
+ local $foo = 9; # blows up
+
+The local() generated a compile-time error because you just touched a global
+name without fully qualifying it.
+
+=item C<strict subs>
+
+This disables the poetry optimization,
+generating a compile-time error if you
+try to use a bareword identifier that's not a subroutine.
+
+ use strict 'subs';
+ $SIG{PIPE} = Plumber; # blows up
+ $SIG{"PIPE"} = "Plumber"; # just fine
+
+=back
+
+See L<perlmod/Pragmatic Modules>.
+
+
+=cut
+
sub bits {
my $bits = 0;
foreach $sememe (@_) {