/usr/lib/x86_64-linux-gnu/perl5/5.26/signatures.pm is in libsignatures-perl 0.13-2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 | use strict;
use warnings;
package signatures; # git description: v0.12-5-gde90008
# ABSTRACT: Subroutine signatures with no source filter
our $VERSION = '0.13';
use XSLoader;
use B::Hooks::Parser 0.12;
use B::Hooks::OP::Check 0.17;
use B::Hooks::OP::PPAddr 0.03;
use B::Hooks::EndOfScope 0.08 ();
XSLoader::load(
__PACKAGE__,
$VERSION,
);
{
my %pkgs;
sub import {
my ($class) = @_;
my $caller = caller();
$pkgs{$caller} = $class->setup_for($caller);
return;
}
sub unimport {
my ($class) = @_;
my $caller = caller();
$class->teardown_for(delete $pkgs{$caller});
return;
}
}
sub setup_for {
my ($class, $caller) = @_;
my $ret = $class->setup($caller);
$^H{"${class}::enabled"} = 1;
my $old_warn = $SIG{__WARN__};
$SIG{__WARN__} = sub {
if ($_[0] !~ /^(?:(?:Illegal character in prototype)|(?:Prototype after '.')) for /) {
$old_warn ? $old_warn->(@_) : warn @_;
}
};
my $unregister;
{
my $called = 0;
$unregister = sub {
return if $called++;
$class->teardown_for([$ret, $unregister]);
$SIG{__WARN__} = $old_warn;
};
}
&B::Hooks::EndOfScope::on_scope_end($unregister);
return [$ret, $unregister];
}
sub teardown_for {
my ($class, $data) = @_;
delete $^H{"${class}::enabled"};
$class->teardown($data->[0]);
$data->[1]->();
return;
}
sub callback {
my ($class, $offset, $proto) = @_;
my $inject = $class->proto_unwrap($proto);
$class->inject($offset, $inject);
return;
}
sub proto_unwrap {
my ($class, $proto) = @_;
return '' unless length $proto;
return "my ($proto) = \@_;";
}
sub inject {
my ($class, $offset, $inject) = @_;
my $linestr = B::Hooks::Parser::get_linestr();
substr($linestr, $offset + 1, 0) = $inject;
B::Hooks::Parser::set_linestr($linestr);
return;
}
1;
__END__
=pod
=encoding UTF-8
=head1 NAME
signatures - Subroutine signatures with no source filter
=head1 VERSION
version 0.13
=head1 SYNOPSIS
use signatures;
sub foo ($bar, $baz) {
return $bar + $baz;
}
=head1 DESCRIPTION
With this module, we can specify subroutine signatures and have variables
automatically defined within the subroutine.
For example, you can write
sub square ($num) {
return $num * $num;
}
and it will be automatically turned into the following at compile time:
sub square {
my ($num) = @_;
return $num * $num;
}
Note that, although the syntax is very similar, the signatures provided by this
module are not to be confused with the prototypes described in L<perlsub>. All
this module does is extracting items of @_ and assigning them to the variables
in the parameter list. No argument validation is done at runtime.
The signature definition needs to be on a single line only.
If you want to combine sub signatures with regular prototypes a C<proto>
attribute exists:
sub foo ($bar, $baz) : proto($$) { ... }
=head1 METHODS
If you want subroutine signatures doing something that this module doesn't
provide, like argument validation, typechecking and similar, you can subclass
it and override the following methods.
=head2 proto_unwrap ($prototype)
Turns the extracted C<$prototype> into code.
The default implementation returns C<< my (${prototype}) = @_; >> or an empty
string, if no prototype is given.
=head2 inject ($offset, $code)
Inserts a C<$code> string into the line perl currently parses at the given
C<$offset>. This is only called by the C<callback> method.
=head2 callback ($offset, $prototype)
This gets called as soon as a sub definition with a prototype is
encountered. Arguments are the C<$offset> within the current line perl
is parsing and extracted C<$prototype>.
The default implementation calls C<proto_unwrap> with the prototype and passes
the returned value and the offset to C<inject>.
=for Pod::Coverage setup setup_for teardown teardown_for
=head1 BUGS
=over 4
=item prototypes aren't checked for validity yet
You won't get a warning for invalid prototypes using the C<proto> attribute,
like you normally would with warnings enabled.
=item you shouldn't alter $SIG{__WARN__} at compile time
After this module is loaded you shouldn't make any changes to C<$SIG{__WARN__}>
during compile time. Changing it before the module is loaded or at runtime is
fine.
=back
=head1 SEE ALSO
L<Method::Signatures>
L<MooseX::Method::Signatures>
L<Sub::Signatures>
L<Attribute::Signature>
L<Perl6::Subs>
L<Perl6::Parameters>
=head1 THANKS
=for stopwords Moritz Lenz Steffen Schwigon
Moritz Lenz and Steffen Schwigon for documentation review and
improvement.
=head1 AUTHOR
Florian Ragwitz <rafl@debian.org>
=head1 CONTRIBUTORS
=for stopwords Karen Etheridge Peter Martini Alexandr Ciornii Father Chrysostomos Alex Kapranoff Steffen Schwigon
=over 4
=item *
Karen Etheridge <ether@cpan.org>
=item *
Peter Martini <PeterCMartini@GMail.com>
=item *
Alexandr Ciornii <alexchorny@gmail.com>
=item *
Father Chrysostomos <sprout@cpan.org>
=item *
Alex Kapranoff <alex@kapranoff.ru>
=item *
Steffen Schwigon <ss5@renormalist.net>
=back
=head1 COPYRIGHT AND LICENSE
This software is copyright (c) 2008 by Florian Ragwitz.
This is free software; you can redistribute it and/or modify it under
the same terms as the Perl 5 programming language system itself.
=cut
|