Devel::Isa::Explainer - Pretty Print Hierarchies of Subs in Packages
version 0.002901
use Devel::Isa::Explainer qw( explain_isa );
# Load it yourself first
print explain_isa('Dist::Zilla::Dist::Builder');
This module is a simple tool for quickly visualizing inheritance hierarchies to quickly see what subs are available for a given package, or to ascertain where a given sub you might see in use is coming from.
This module does not concern itself with any of the fanciness of Roles, and instead, relies entirely on standard Perl5 Object Model infrastructure. ( Roles are effectively invisible at run-time as they appear as composed subs in the corresponding class )
This module utilizes a cultural understanding of the naming conventions that are standardized
on CPAN
, and applies color highlighting to make them stand out.
For instance:
- all lower case subs are assumed to be normal methods/functions/subs
- all upper case subs are assumed to be used for semi-private inter-module interoperability
( for instance,
DESTROY
,BUILDALL
) - subs with a leading underscore are assumed to be private methods/functions/subs
- subs with
CamelCase
naming are assumed to be uncleaned Moose/Types::Tiny type-constraint subs - subs starting with
is_
to_
andassert_
followed byCamelCase
lettering are assumed to be uncleaned type-constraint utility subs.
This module analyses the presence of "Shadowed" subs by indicating specifically when a given module has an overriding sub in higher context.
We don't do any work to ascertain if in fact the higher sub chains to the shadowed one or not, but we merely indicate that there's a possibility, and show where the default method call will get routed on the relevant class.
print explain_isa( $loaded_module_name );
Returns a pretty-printed formatted description of the class referenced by $loaded_module_name
explain_isa()
expects exactly one argument, a (loaded) module name to print
the ISA
hierarchy of. You passed either 0 arguments ( too few to be useful )
or too many ( Which silently ignoring might block us from adding future enhancements )
explain_isa( $argument )
expects $argument
to be a defined module name, but you
somehow managed to pass undef
. I don't think there is a legitimate use case for a
module with an undefined name, but I could be wrong.
File a bug if you have proof.
explain_isa( $argument )
expects $argument
to have a positive length, but you passed
an empty string. Again as with (id: Devel::Isa::Explainer#2)
, file a bug if there's a
real use case here that I missed.
explain_isa( $argument )
expects $argument
to be a normal scalar value describing
a module name, but you passed a reference of some kind.
This is presently an error to protect it for future possible use.
When trying to extract subs and inheritance from the module name you passed in
explain_isa( $module_name )
, no sub
s could be found, there were no parent classes,
and the module name in question had never been registered in %INC
by Perl.
This indicates that the most likely thing that happened was you forgot to either require
the module in question first, or you forgot to locally define that package with some classes
prior to calling explain_isa( $module_name )
Kent Fredric kentnl@cpan.org
This software is copyright (c) 2016 by Kent Fredric kentfredric@gmail.com.
This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.