./devel/p5-circular-require, Perl5 module to detect circularity in use/require statements

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Branch: pkgsrc-2022Q3, Version: 0.12nb5, Package name: p5-circular-require-0.12nb5, Maintainer: pkgsrc-users

Perl by default just ignores cycles in require statements - if Foo.pm does
use Bar and Bar.pm does use Foo, doing use Foo elsewhere will start loading
Foo.pm, then hit the use statement, start loading Bar.pm, hit the use
statement, notice that Foo.pm has already started loading and ignore it,
and continue loading Bar.pm. But Foo.pm hasn't finished loading yet, so if
Bar.pm uses anything from Foo.pm (which it likely does, if it's loading it),
those won't be accessible while the body of Bar.pm is being executed. This
can lead to some very confusing errors, especially if introspection is
happening at load time (make_immutable in Moose classes, for example). This
module generates a warning whenever a module is skipped due to being loaded,
if that module has not finished executing.

This module works as a pragma, and typically pragmas have lexical scope.
Lexical scope doesn't make a whole lot of sense for this case though,
because the effect it's tracking isn't lexical (what does it mean to disable
the pragma inside of a cycle vs. outside of a cycle? does disabling it
within a cycle cause it to always be disabled for that cycle, or only if
it's disabled at the point where the warning would otherwise be generated?
etc.), but dynamic scope (the scope that, for instance, local uses) does,
and that's how this module works. Saying no circular::require enables the
module for the current dynamic scope, and use circular::require disables
it for the current dynamic scope. Hopefully, this will just do what you mean.


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