- EXPORTED FUNCTIONS
- SEE ALSO
- LICENSE AND COPYRIGHT
Module::Lazy - postpone loading a module until it's actually used
use Module::Lazy "My::Module"; # My::Module has not been loaded my $var = My::Module->new; # My::Module is loaded now, and new() method is called no Module::Lazy; # Force loading of all postponed modules
In large projects loading all the dependencies may take a lot of time. This module attempts to reduce the startup time by postponing initialization. The improvement be significant for unit test scripts and small command-line tools which do not utilize all the functionality at once.
This comes at a cost of reduced stability, as load-time errors are also postponed. The
no Module::Lazy directive is provided to mitigate the risk by forcing the pending modules to load.
use Module::Lazy "Some::Module"; is called, the module in question is not loaded. A stub package with the same name is created instead.
Should any method call be performed on the stub package, it loads the original one and jumps to respective method.
isa() are overloaded and will trigger module loading.
import is not called on the target package. This MAY change in the future.
No extra options (except from target module name) are allowed.
no Module::Lazy; or, alternatively,
Module::Lazy->unimport; will cause all postponed modules to be loaded immediately, in alphabetical order.
This may be useful to avoid deferred errors and/or side effects of module loading.
No extra options to unimport are supported.
PERL_LAZYLOAD_DEBUG is set and true, warns about module loading via Carp.
PERL_LAZYLOAD_DISABLE is set and true, don't try to lazyload anything - just go straight to
(That's roughly equivalent to
perl -M-Module::Lazy on command line).
The following symbols are currently replaced by stubs in the module to be loaded:
If a module was ever lazyloaded, a normal
requirewould do nothing. A method must be called to inflate the module.
This is done so because a normal require would partially overwrite stub methods and potentially wreak havoc.
A fake $VERSION = 10**9 is generated so that
use Module x.yydoesn't die. This value is erased before actually loading the module.
use mro 'c3';does not work with lazy-loaded parent classes.
import()is not called on the modules being loaded. The decision is yet to be made whether it's good or bad.
no way to preload prototyped exported functions (that's what autouse does), but maybe there should be?
certainly not enough interoperability tests.
Please report bugs via github or RT:
bug-module-lazy at rt.cpan.org
You can find documentation for this module with the
You can also look for information at:
RT: CPAN's request tracker (report bugs here)
AnnoCPAN: Annotated CPAN documentation
autouse is another module with similar idea, however, it does it for imported functions rather than methods.
Copyright 2019 Konstantin S. Uvarin,
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