Sub::Exporter::ForMethods - helper routines for using Sub::Exporter to build methods
version 0.100052
In an exporting library:
package Method::Builder;
use Sub::Exporter::ForMethods qw(method_installer);
use Sub::Exporter -setup => {
exports => [ method => \'_method_generator' ],
installer => method_installer,
};
sub _method_generator {
my ($self, $name, $arg, $col) = @_;
return sub { ... };
};
In an importing library:
package Vehicle::Autobot;
use Method::Builder method => { -as => 'transform' };
The synopsis section, above, looks almost indistinguishable from any other
use of Sub::Exporter, apart from the use of
method_installer . It is nearly indistinguishable in behavior, too. The
only change is that subroutines exported from Method::Builder into named slots
in Vehicle::Autobot will be wrapped in a subroutine called
Vehicle::Autobot::transform . This will insert a named frame into stack
traces to aid in debugging.
More importantly (for the author, anyway), they will not be removed by
namespace::autoclean. This makes the following code
work:
package MyLibrary;
use Math::Trig qw(tan); # uses Exporter.pm
use String::Truncate qw(trunc); # uses Sub::Exporter's defaults
use Sub::Exporter::ForMethods qw(method_installer);
use Mixin::Linewise { installer => method_installer }, qw(read_file);
use namespace::autoclean;
...
1;
After MyLibrary is compiled, namespace::autoclean will remove tan and
trunc as foreign contaminants, but will leave read_file in place. It
will also remove method_installer , an added win.
Sub::Exporter::ForMethods offers only one routine for export, and it may also
be called by its full package name:
my $installer = method_installer(\%arg);
This routine returns an installer suitable for use as the installer argument
to Sub::Exporter. It updates the \@to_export argument to wrap all code that
will be installed by name in a named subroutine, then passes control to the
default Sub::Exporter installer.
The only argument to method_installer is an optional hashref which may
contain a single entry for rebless . If the value for rebless is true,
when a blessed subroutine is wrapped, the wrapper will be blessed into the same
package.
Ricardo Signes <rjbs@cpan.org>
This software is copyright (c) 2015 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.
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