X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2Fvars.pm;h=a0151b8403072b3bdced7cd97030cacc9e36763f;hb=18d238e4a14a835312fdd656a58d80d51ab487e2;hp=0b7dacc7511fe59a921e4fc42463ad792f1e5222;hpb=3561ff8967661c363e907527e81e69a79a1e4ef2;p=p5sagit%2Fp5-mst-13.2.git diff --git a/lib/vars.pm b/lib/vars.pm index 0b7dacc..a0151b8 100644 --- a/lib/vars.pm +++ b/lib/vars.pm @@ -1,8 +1,54 @@ package vars; +use 5.006; + +our $VERSION = '1.01'; + +use warnings::register; +use strict qw(vars subs); + +sub import { + my $callpack = caller; + my ($pack, @imports) = @_; + my ($sym, $ch); + foreach (@imports) { + if (($ch, $sym) = /^([\$\@\%\*\&])(.+)/) { + if ($sym =~ /\W/) { + # time for a more-detailed check-up + if ($sym =~ /^\w+[[{].*[]}]$/) { + require Carp; + Carp::croak("Can't declare individual elements of hash or array"); + } elsif (warnings::enabled() and length($sym) == 1 and $sym !~ tr/a-zA-Z//) { + warnings::warn("No need to declare built-in vars"); + } elsif (($^H &= strict::bits('vars'))) { + require Carp; + Carp::croak("'$_' is not a valid variable name under strict vars"); + } + } + $sym = "${callpack}::$sym" unless $sym =~ /::/; + *$sym = + ( $ch eq "\$" ? \$$sym + : $ch eq "\@" ? \@$sym + : $ch eq "\%" ? \%$sym + : $ch eq "\*" ? \*$sym + : $ch eq "\&" ? \&$sym + : do { + require Carp; + Carp::croak("'$_' is not a valid variable name"); + }); + } else { + require Carp; + Carp::croak("'$_' 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 +56,10 @@ vars - Perl pragma to predeclare global variable names =head1 DESCRIPTION +NOTE: For variables in the current package, the functionality provided +by this pragma has been superseded by C declarations, available +in Perl v5.6.0 or later. See L. + 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. @@ -19,34 +69,14 @@ C declarations are not BLOCK-scoped. They are thus effective for the entire file in which they appear. You may not rescind such declarations with C or C. -Packages such as the B and B that delay loading -of subroutines within packages can create problems with package lexicals -defined using C. While the B pragma cannot duplicate the -effect of package lexicals (total transparency outside of the package), -it can act as an acceptable substitute by pre-declaring global symbols, -ensuring their availability to to the later-loaded routines. +Packages such as the B and B that delay +loading of subroutines within packages can create problems with +package lexicals defined using C. While the B pragma +cannot duplicate the effect of package lexicals (total transparency +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. +See L. =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;