Re^4: "Useless use of a constant" in grep block?

When something is (indeed) a warning, there's always the possibility that the warning is incorrect in that it does not align with what the user means. But this alone does not invalidate the fact said warning is useful. For example, using another warning that has "possibly" in its wording:

% perl -Mstrict -MFoo -we'$Foo::bar = 1'
Name "Foo::bar" used only once: possible typo at -e line 1.
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Does the programmer make a typo or does he really mean setting $Foo::bar? perl can never know for sure, so it just emits a warning instead of an error message. The programmer can disable the warning if he knows that he is doing what he wants. Continuing with another warning which you mentioned:

our @EXPORT = qw(
    foo bar baz
    qux quux
);
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and a few months later:

our @EXPORT = qw(
    foo bar baz
    qux quux
    corge grault
    # not sure we want to export these by default because the name is 
+rather common, 
    # but let's do it anyways for now
    thud jet
);
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Are you sure that you, even if you're already a veteran, will never make this mistake? perl is being helpful here by emitting a warning. If perl turns out to be wrong here, just disable the warning lexically.

But I guess there's always the debate of how much should perl offer helping hands and treat the programmer like a novice or stupid person. But hey, humans *are* stupid :)

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Re^5: "Useless use of a constant" in grep block? by Anonymous Monk on Aug 04, 2017 at 10:14 UTC
and a few months later: our @EXPORT ... Are you sure that you, even if you're already a veteran, will never make this mistake? comments next to a space separated list of barewords? Yes, I am 100% sure I will never make this mistake the same as I am sure I will never type "#oops," and not want the "#" and "," as part of the string, and then come back 20 years later and type "# oh yeah , yeah yeah yeah " and expect to get a list instead of a string but even if I made the mistake, Exporter whose job it is to handle @EXPORT, would catch this the first time the module was used, like when the tests were run, and die `Can't export symbol: # at junk.pl line 21` But hey, documenting design indecision in comments? That doesn't belong in comments, it belongs in official documentation, so I'm more than 100% sure, i'm 200% sure :D Does the programmer make a typo or does he really mean setting $Foo::bar? When something is (indeed) a warning, there's always the possibility that the warning is incorrect in that it does not align with what the user means. congratulations, , even I won't argue that one doesn't belong, but only because its exceptional Solution to that one isn't disable warnings lexically its `$double::up = $double::up = "for silence";` Anyway , haukex was faster to perlcritic policy, but I would have used xpaths instead perlcritic is where this type of extra help belongs , warnings is all full up	[reply] [d/l] [select]
Re^5: "Useless use of a constant" in grep block? by Anonymous Monk on Aug 03, 2017 at 12:00 UTC
Disingenuous	[reply]