Devel::BeginLift - make selected sub calls evaluate at compile time
use Devel::BeginLift qw(foo baz); use vars qw($i); BEGIN { $i = 0 } sub foo { "foo: $_[0]\n"; } sub bar { "bar: $_[0]\n"; } for (1 .. 3) { print foo($i++); print bar($i++); } no Devel::BeginLift; print foo($i++);
outputs -
foo: 0 bar: 1 foo: 0 bar: 2 foo: 0 bar: 3 foo: 4
Devel::BeginLift 'lifts' arbitrary sub calls to running at compile time - sort of a souped up version of "use constant". It does this via some slightly insane perlguts magic.
use Devel::BeginLift qw(list of subs);
Calls Devel::BeginLift->setup_for(__PACKAGE__ => \@list_of_subs);
no Devel::BeginLift;
Calls Devel::BeginLift->teardown_for(__PACKAGE__);
Devel::BeginLift->setup_for($package => \@subnames);
Installs begin lifting magic (unless already installed) and registers "${package}::$name" for each member of @subnames to be executed when parsed and replaced with its output rather than left for runtime.
Devel::BeginLift->teardown_for($package);
Deregisters all subs currently registered for $package and uninstalls begin lifting magic is number of teardown_for calls matches number of setup_for calls.
$id = Devel::BeginLift->setup_for_cv(\&code);
Same as setup_for, but only registers begin lifting magic for one code reference. Returns an id to be used in teardown_for_cv.
setup_for
teardown_for_cv
Devel::BeginLift->teardown_for_cv($id);
Deregisters begin lifting magic referred to by $id.
$id
Matt S Trout - <mst@shadowcatsystems.co.uk>
Company: http://www.shadowcatsystems.co.uk/ Blog: http://chainsawblues.vox.com/
This library is free software under the same terms as perl itself
To install Devel::BeginLift, copy and paste the appropriate command in to your terminal.
cpanm
cpanm Devel::BeginLift
CPAN shell
perl -MCPAN -e shell install Devel::BeginLift
For more information on module installation, please visit the detailed CPAN module installation guide.