X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2Fstrict.pm;h=d1479ed865ee1dd4c627f6d08ec90728f628c70c;hb=dd5ea221bb13f4bad856ba91d1a82acf3ec12919;hp=99ed01d5838313ba7cb50551f04a923e5a7e07ca;hpb=1d7c184104c076988718a01b77c8706aae05b092;p=p5sagit%2Fp5-mst-13.2.git diff --git a/lib/strict.pm b/lib/strict.pm index 99ed01d..d1479ed 100644 --- a/lib/strict.pm +++ b/lib/strict.pm @@ -1,5 +1,40 @@ package strict; +$strict::VERSION = "1.02"; + +my %bitmask = ( +refs => 0x00000002, +subs => 0x00000200, +vars => 0x00000400 +); + +sub bits { + my $bits = 0; + my @wrong; + foreach my $s (@_) { + push @wrong, $s unless exists $bitmask{$s}; + $bits |= $bitmask{$s} || 0; + } + if (@wrong) { + require Carp; + Carp::croak("Unknown 'strict' tag(s) '@wrong'"); + } + $bits; +} + +sub import { + shift; + $^H |= bits(@_ ? @_ : qw(refs subs vars)); +} + +sub unimport { + shift; + $^H &= ~ bits(@_ ? @_ : qw(refs subs vars)); +} + +1; +__END__ + =head1 NAME strict - Perl pragma to restrict unsafe constructs @@ -34,12 +69,22 @@ use symbolic references (see L). print $$ref; # ok $ref = "foo"; print $$ref; # runtime error; normally ok + $file = "STDOUT"; + print $file "Hi!"; # error; note: no comma after $file + +There is one exception to this rule: + + $bar = \&{'foo'}; + &$bar; + +is allowed so that C would not break under stricture. + =item C This generates a compile-time error if you access a variable that wasn't -declared via C, -localized via C or wasn't fully qualified. Because this is to avoid +declared via "our" or C, +localized via C, 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 and L. @@ -50,7 +95,7 @@ L. local $foo = 9; # blows up package Cinna; - use vars qw/ $bar /; # Declares $bar in current package + our $bar; # Declares $bar in current package $bar = 'HgS'; # ok, global declared via pragma The local() generated a compile-time error because you just touched a global @@ -77,31 +122,4 @@ appears in curly braces or on the left hand side of the "=E" symbol. See L. - =cut - -$strict::VERSION = "1.01"; - -my %bitmask = ( -refs => 0x00000002, -subs => 0x00000200, -vars => 0x00000400 -); - -sub bits { - my $bits = 0; - foreach my $s (@_){ $bits |= $bitmask{$s} || 0; }; - $bits; -} - -sub import { - shift; - $^H |= bits(@_ ? @_ : qw(refs subs vars)); -} - -sub unimport { - shift; - $^H &= ~ bits(@_ ? @_ : qw(refs subs vars)); -} - -1;