Bug #86939 for Moo: 'extends' sometimes tries to load modules

Mon Jul 15 06:03:22 2013 MAUKE [...] cpan.org - Ticket created

Subject:

'extends' sometimes tries to load modules

The documentation for 'extends' says: | extends 'Parent::Class'; | | Declares base class. Multiple superclasses can be passed for multiple | inheritance (but please use roles instead). | | Calling extends more than once will REPLACE your superclasses, not add to | them like 'use base' would. What it doesn't say: In addition to setting up inheritance, in some cases[1] it tries to load 'Parent/Class.pm' from disk first. I find this behavior surprising and it doesn't seem to be documented anywhere. I think this behavior should be documented (or alternatively removed). [1] exact logic hard to describe; see sub _load_module in Moo::_Utils

Mon Jul 15 13:29:57 2013 ether [...] cpan.org - Correspondence added

Subject:	Re: [rt.cpan.org #86939] 'extends' sometimes tries to load modules
Date:	Mon, 15 Jul 2013 10:29:45 -0700
To:	Lukas Mai via RT <bug-Moo [...] rt.cpan.org>
From:	Karen Etheridge <ether [...] cpan.org>

On Mon, Jul 15, 2013 at 06:03:23AM -0400, Lukas Mai via RT wrote: Show quoted text

> What it doesn't say: In addition to setting up inheritance, in some cases[1] it > tries to load 'Parent/Class.pm' from disk first. I find this behavior > surprising and it doesn't seem to be documented anywhere. > > I think this behavior should be documented (or alternatively removed).

It can certainly be documented. I'm not sure why it should be confusing though, as 'use parent' and 'use base' also load the module first if it isn't already in %INC.

Mon Jul 15 13:29:58 2013 The RT System itself - Status changed from 'new' to 'open'

Mon Jul 15 14:09:29 2013 haarg [...] haarg.org - Correspondence added

The heuristic it uses is different from what both base and parent do though, so it's probably worth mentioning.

Mon Jul 15 14:16:19 2013 MAUKE [...] cpan.org - Correspondence added

On Mon Jul 15 13:29:57 2013, ETHER wrote: Show quoted text

> On Mon, Jul 15, 2013 at 06:03:23AM -0400, Lukas Mai via RT wrote:

> > What it doesn't say: In addition to setting up inheritance, in some

> cases[1] it

> > tries to load 'Parent/Class.pm' from disk first. I find this

> behavior

> > surprising and it doesn't seem to be documented anywhere. > > > > I think this behavior should be documented (or alternatively

> removed). > > It can certainly be documented. I'm not sure why it should be > confusing > though, as 'use parent' and 'use base' also load the module first if > it > isn't already in %INC.

It's confusing because 'extends' is not described as being like base/parent; it's described as declaring base classes, which I understand to be like '@ISA = ...'. The documentation for base/parent says: "Allows you to both load one or more modules, while setting up inheritance from those modules at the same time." ... i.e. it emphasizes the module loading part that 'extends' doesn't even mention.

Fri Dec 06 07:03:44 2013 haarg [...] haarg.org - Correspondence added

The behavior of this has been changed somewhat. It now always tries to load extends/with modules, but still continues without error if the module doesn't exist but its stash has subs. The documentation has been updated to reflect this.

Fri Dec 06 07:03:46 2013 haarg [...] haarg.org - Status changed from 'open' to 'patched'

Thu Dec 26 22:05:33 2013 haarg [...] haarg.org - Correspondence added

Resolved in 1.004000.

Thu Dec 26 22:05:34 2013 haarg [...] haarg.org - Status changed from 'patched' to 'resolved'

Thu Dec 26 22:05:34 2013 haarg [...] haarg.org - Fixed in 1.004000 added