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use warnings 'shadow-package'
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| # detected by mziescha | |
| use warnings 'shadow-package'; # or just shadow | |
| package Acme::Test; | |
| sub new { bless {}, shift } | |
| sub Sub { 'shadowed' } | |
| package Acme::Test::Sub; | |
| sub new { print 'Sub'; bless {}, shift } # warn: "Package Acme::Test::Sub shadowed by Acme::Test->Sub at warn-shadow-pkg.pl, line 8" | |
| package main; | |
| # calls &Acme::Test:: Sub, then ->new, not &Acme::Test::Sub -> new | |
| Acme::Test::Sub->new(); # warn: "Subroutine &Acme::Test::Sub shadowed by Acme::Test->Sub at warn-shadow-pkg.pl, line 13" | |
| =pod | |
| Note that Acme::Test::Sub is written in package and subroutine syntax it is still | |
| taken as static method call, overriding the existing package. | |
| With use warnings 'shadow-package' or 'shadow' | |
| warn about when | |
| * adding a new package shadowed by an existing method (at compile-time) | |
| * adding a method shadowing an existing package (at compile-time) | |
| * calling a method shadowing an existing package-sub (at compile-time) | |
| No warning at run-time? Or only when not already warned before. | |
| This would be needed for computed method names, if it still shadows the package then. | |
| tracked at https://github.com/perl11/cperl/issues/368 | |
| =cut |
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Open points:
In the calling case. Use which location? The callers location to see the wrong usage, or the definition of the shadower: file, line 6 or both? "&Acme::Test::Sub shadowed by Acme::Test->Sub defined at warn-shadow-pkg.pl, line 6 at warn-shadow-pkg.pl, line 13", na
name of the warning? it should be in the shadow category. so when you
use warnings 'shadow';it should be enabled.the other case of shadow warnings would be variables being shadowed. These are not so severe as packages.
compile-time only, or also at run-time? In C such warnings are compile-time only (of course). But compile-time only would miss all the cases with computed method-names, which could also be shadowed.
Tracked at perl11/cperl#368