use strict;
use warnings;
package Sub::Install;
# ABSTRACT: install subroutines into packages easily
$Sub::Install::VERSION = '0.928';
use Carp;
use Scalar::Util ();
#pod =head1 SYNOPSIS
#pod
#pod use Sub::Install;
#pod
#pod Sub::Install::install_sub({
#pod code => sub { ... },
#pod into => $package,
#pod as => $subname
#pod });
#pod
#pod =head1 DESCRIPTION
#pod
#pod This module makes it easy to install subroutines into packages without the
#pod unsightly mess of C<no strict> or typeglobs lying about where just anyone can
#pod see them.
#pod
#pod =func install_sub
#pod
#pod Sub::Install::install_sub({
#pod code => \&subroutine,
#pod into => "Finance::Shady",
#pod as => 'launder',
#pod });
#pod
#pod This routine installs a given code reference into a package as a normal
#pod subroutine. The above is equivalent to:
#pod
#pod no strict 'refs';
#pod *{"Finance::Shady" . '::' . "launder"} = \&subroutine;
#pod
#pod If C<into> is not given, the sub is installed into the calling package.
#pod
#pod If C<code> is not a code reference, it is looked for as an existing sub in the
#pod package named in the C<from> parameter. If C<from> is not given, it will look
#pod in the calling package.
#pod
#pod If C<as> is not given, and if C<code> is a name, C<as> will default to C<code>.
#pod If C<as> is not given, but if C<code> is a code ref, Sub::Install will try to
#pod find the name of the given code ref and use that as C<as>.
#pod
#pod That means that this code:
#pod
#pod Sub::Install::install_sub({
#pod code => 'twitch',
#pod from => 'Person::InPain',
#pod into => 'Person::Teenager',
#pod as => 'dance',
#pod });
#pod
#pod is the same as:
#pod
#pod package Person::Teenager;
#pod
#pod Sub::Install::install_sub({
#pod code => Person::InPain->can('twitch'),
#pod as => 'dance',
#pod });
#pod
#pod =func reinstall_sub
#pod
#pod This routine behaves exactly like C<L</install_sub>>, but does not emit a
#pod warning if warnings are on and the destination is already defined.
#pod
#pod =cut
sub _name_of_code {
my ($code) = @_;
require B;
my $name = B::svref_2object($code)->GV->NAME;
return $name unless $name =~ /\A__ANON__/;
return;
}
# See also Params::Util, to which this code was donated.
sub _CODELIKE {
(Scalar::Util::reftype($_[0])||'') eq 'CODE'
|| Scalar::Util::blessed($_[0])
&& (overload::Method($_[0],'&{}') ? $_[0] : undef);
}
# do the heavy lifting
sub _build_public_installer {
my ($installer) = @_;
sub {
my ($arg) = @_;
my ($calling_pkg) = caller(0);
# I'd rather use ||= but I'm whoring for Devel::Cover.
for (qw(into from)) { $arg->{$_} = $calling_pkg unless $arg->{$_} }
# This is the only absolutely required argument, in many cases.
Carp::croak "named argument 'code' is not optional" unless $arg->{code};
if (_CODELIKE($arg->{code})) {
$arg->{as} ||= _name_of_code($arg->{code});
} else {
Carp::croak
"couldn't find subroutine named $arg->{code} in package $arg->{from}"
unless my $code = $arg->{from}->can($arg->{code});
$arg->{as} = $arg->{code} unless $arg->{as};
$arg->{code} = $code;
}
Carp::croak "couldn't determine name under which to install subroutine"
unless $arg->{as};
$installer->(@$arg{qw(into as code) });
}
}
# do the ugly work
my $_misc_warn_re;
my $_redef_warn_re;
BEGIN {
$_misc_warn_re = qr/
Prototype\ mismatch:\ sub\ .+? |
Constant subroutine .+? redefined
/x;
$_redef_warn_re = qr/Subroutine\ .+?\ redefined/x;
}
my $eow_re;
BEGIN { $eow_re = qr/ at .+? line \d+\.\Z/ };
sub _do_with_warn {
my ($arg) = @_;
my $code = delete $arg->{code};
my $wants_code = sub {
my $code = shift;
sub {
my $warn = $SIG{__WARN__} ? $SIG{__WARN__} : sub { warn @_ }; ## no critic
local $SIG{__WARN__} = sub {
my ($error) = @_;
for (@{ $arg->{suppress} }) {
return if $error =~ $_;
}
for (@{ $arg->{croak} }) {
if (my ($base_error) = $error =~ /\A($_) $eow_re/x) {
Carp::croak $base_error;
}
}
for (@{ $arg->{carp} }) {
if (my ($base_error) = $error =~ /\A($_) $eow_re/x) {
return $warn->(Carp::shortmess $base_error);
}
}
($arg->{default} || $warn)->($error);
};
$code->(@_);
};
};
return $wants_code->($code) if $code;
return $wants_code;
}
sub _installer {
sub {
my ($pkg, $name, $code) = @_;
no strict 'refs'; ## no critic ProhibitNoStrict
*{"$pkg\::$name"} = $code;
return $code;
}
}
BEGIN {
*_ignore_warnings = _do_with_warn({
carp => [ $_misc_warn_re, $_redef_warn_re ]
});
*install_sub = _build_public_installer(_ignore_warnings(_installer));
*_carp_warnings = _do_with_warn({
carp => [ $_misc_warn_re ],
suppress => [ $_redef_warn_re ],
});
*reinstall_sub = _build_public_installer(_carp_warnings(_installer));
*_install_fatal = _do_with_warn({
code => _installer,
croak => [ $_redef_warn_re ],
});
}
#pod =func install_installers
#pod
#pod This routine is provided to allow Sub::Install compatibility with
#pod Sub::Installer. It installs C<install_sub> and C<reinstall_sub> methods into
#pod the package named by its argument.
#pod
#pod Sub::Install::install_installers('Code::Builder'); # just for us, please
#pod Code::Builder->install_sub({ name => $code_ref });
#pod
#pod Sub::Install::install_installers('UNIVERSAL'); # feeling lucky, punk?
#pod Anything::At::All->install_sub({ name => $code_ref });
#pod
#pod The installed installers are similar, but not identical, to those provided by
#pod Sub::Installer. They accept a single hash as an argument. The key/value pairs
#pod are used as the C<as> and C<code> parameters to the C<install_sub> routine
#pod detailed above. The package name on which the method is called is used as the
#pod C<into> parameter.
#pod
#pod Unlike Sub::Installer's C<install_sub> will not eval strings into code, but
#pod will look for named code in the calling package.
#pod
#pod =cut
sub install_installers {
my ($into) = @_;
for my $method (qw(install_sub reinstall_sub)) {
my $code = sub {
my ($package, $subs) = @_;
my ($caller) = caller(0);
my $return;
for (my ($name, $sub) = %$subs) {
$return = Sub::Install->can($method)->({
code => $sub,
from => $caller,
into => $package,
as => $name
});
}
return $return;
};
install_sub({ code => $code, into => $into, as => $method });
}
}
#pod =head1 EXPORTS
#pod
#pod Sub::Install exports C<install_sub> and C<reinstall_sub> only if they are
#pod requested.
#pod
#pod =head2 exporter
#pod
#pod Sub::Install has a never-exported subroutine called C<exporter>, which is used
#pod to implement its C<import> routine. It takes a hashref of named arguments,
#pod only one of which is currently recognize: C<exports>. This must be an arrayref
#pod of subroutines to offer for export.
#pod
#pod This routine is mainly for Sub::Install's own consumption. Instead, consider
#pod L<Sub::Exporter>.
#pod
#pod =cut
sub exporter {
my ($arg) = @_;
my %is_exported = map { $_ => undef } @{ $arg->{exports} };
sub {
my $class = shift;
my $target = caller;
for (@_) {
Carp::croak "'$_' is not exported by $class" if !exists $is_exported{$_};
install_sub({ code => $_, from => $class, into => $target });
}
}
}
BEGIN { *import = exporter({ exports => [ qw(install_sub reinstall_sub) ] }); }
#pod =head1 SEE ALSO
#pod
#pod =over
#pod
#pod =item L<Sub::Installer>
#pod
#pod This module is (obviously) a reaction to Damian Conway's Sub::Installer, which
#pod does the same thing, but does it by getting its greasy fingers all over
#pod UNIVERSAL. I was really happy about the idea of making the installation of
#pod coderefs less ugly, but I couldn't bring myself to replace the ugliness of
#pod typeglobs and loosened strictures with the ugliness of UNIVERSAL methods.
#pod
#pod =item L<Sub::Exporter>
#pod
#pod This is a complete Exporter.pm replacement, built atop Sub::Install.
#pod
#pod =back
#pod
#pod =head1 EXTRA CREDITS
#pod
#pod Several of the tests are adapted from tests that shipped with Damian Conway's
#pod Sub-Installer distribution.
#pod
#pod =cut
1;
__END__
=pod
=encoding UTF-8
=head1 NAME
Sub::Install - install subroutines into packages easily
=head1 VERSION
version 0.928
=head1 SYNOPSIS
use Sub::Install;
Sub::Install::install_sub({
code => sub { ... },
into => $package,
as => $subname
});
=head1 DESCRIPTION
This module makes it easy to install subroutines into packages without the
unsightly mess of C<no strict> or typeglobs lying about where just anyone can
see them.
=head1 FUNCTIONS
=head2 install_sub
Sub::Install::install_sub({
code => \&subroutine,
into => "Finance::Shady",
as => 'launder',
});
This routine installs a given code reference into a package as a normal
subroutine. The above is equivalent to:
no strict 'refs';
*{"Finance::Shady" . '::' . "launder"} = \&subroutine;
If C<into> is not given, the sub is installed into the calling package.
If C<code> is not a code reference, it is looked for as an existing sub in the
package named in the C<from> parameter. If C<from> is not given, it will look
in the calling package.
If C<as> is not given, and if C<code> is a name, C<as> will default to C<code>.
If C<as> is not given, but if C<code> is a code ref, Sub::Install will try to
find the name of the given code ref and use that as C<as>.
That means that this code:
Sub::Install::install_sub({
code => 'twitch',
from => 'Person::InPain',
into => 'Person::Teenager',
as => 'dance',
});
is the same as:
package Person::Teenager;
Sub::Install::install_sub({
code => Person::InPain->can('twitch'),
as => 'dance',
});
=head2 reinstall_sub
This routine behaves exactly like C<L</install_sub>>, but does not emit a
warning if warnings are on and the destination is already defined.
=head2 install_installers
This routine is provided to allow Sub::Install compatibility with
Sub::Installer. It installs C<install_sub> and C<reinstall_sub> methods into
the package named by its argument.
Sub::Install::install_installers('Code::Builder'); # just for us, please
Code::Builder->install_sub({ name => $code_ref });
Sub::Install::install_installers('UNIVERSAL'); # feeling lucky, punk?
Anything::At::All->install_sub({ name => $code_ref });
The installed installers are similar, but not identical, to those provided by
Sub::Installer. They accept a single hash as an argument. The key/value pairs
are used as the C<as> and C<code> parameters to the C<install_sub> routine
detailed above. The package name on which the method is called is used as the
C<into> parameter.
Unlike Sub::Installer's C<install_sub> will not eval strings into code, but
will look for named code in the calling package.
=head1 EXPORTS
Sub::Install exports C<install_sub> and C<reinstall_sub> only if they are
requested.
=head2 exporter
Sub::Install has a never-exported subroutine called C<exporter>, which is used
to implement its C<import> routine. It takes a hashref of named arguments,
only one of which is currently recognize: C<exports>. This must be an arrayref
of subroutines to offer for export.
This routine is mainly for Sub::Install's own consumption. Instead, consider
L<Sub::Exporter>.
=head1 SEE ALSO
=over
=item L<Sub::Installer>
This module is (obviously) a reaction to Damian Conway's Sub::Installer, which
does the same thing, but does it by getting its greasy fingers all over
UNIVERSAL. I was really happy about the idea of making the installation of
coderefs less ugly, but I couldn't bring myself to replace the ugliness of
typeglobs and loosened strictures with the ugliness of UNIVERSAL methods.
=item L<Sub::Exporter>
This is a complete Exporter.pm replacement, built atop Sub::Install.
=back
=head1 EXTRA CREDITS
Several of the tests are adapted from tests that shipped with Damian Conway's
Sub-Installer distribution.
=head1 AUTHOR
Ricardo SIGNES <rjbs@cpan.org>
=head1 COPYRIGHT AND LICENSE
This software is copyright (c) 2005 by Ricardo SIGNES.
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