Module::Installed::Tiny - Check if a module is installed, with as little code as possible


This document describes version 0.003 of Module::Installed::Tiny (from Perl distribution Module-Installed-Tiny), released on 2016-08-04.


 use Module::Installed::Tiny qw(module_installed module_source);

 # check if a module is available
 if (module_installed "Foo::Bar") {
     # Foo::Bar is available
 } elsif (module_installed "Foo/") {
     # Foo::Baz is available

 # get a module's source code, dies on failure
 my $src = module_source("Foo/");


To check if a module is installed (available), generally the simplest way is to try to require() it:

 if (eval { require Foo::Bar; 1 }) {
     # Foo::Bar is available

However, this actually loads the module. There are some cases where this is not desirable: 1) we have to check a lot of modules (actually loading the modules will take a lot of CPU time and memory; 2) some of the modules conflict with one another and cannot all be loaded; 3) the module is OS specific and might not load under another OS; 4) we simply do not want to execute the module, for security or other reasons.

Module::Installed::Tiny provides a routine module_installed() which works like Perl's require but does not actually load the module.

This module does not require any other module except Exporter.


module_installed($name) => bool

Check that module named $name is available to load. This means that: either the module file exists on the filesystem and searchable in @INC and the contents of the file can be retrieved, or when there is a require hook in @INC, the module's source can be retrieved from the hook.

Note that this does not guarantee that the module can eventually be loaded successfully, as there might be syntax or runtime errors in the module's source. To check for that, one would need to actually load the module using require.

module_source($name) => str

Return module's source code, without actually loading it. Die on failure.


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Source repository is at


Please report any bugs or feature requests on the bugtracker website



Module::Load::Conditional provides check_install which also does what module_installed does, plus can check module version. It also has a couple other knobs to customize its behavior. It's less tiny than Module::Installed::Tiny though.

Module::Path and Module::Path::More. These modules can also be used to check if a module on the filesystem is available. They do not handle require hooks, nor do they actually check that the module file is readable.


perlancar <>


This software is copyright (c) 2016 by
