in reply to Re^2: warnings pragma anomaly
in thread warnings pragma anomaly

As the return value of this expression is returned and checked for truthness, it's not used in a void context.

Are you sure about that? If you end a package with just: 1; no warning is produced; but if you end it with just: 42;:

C:\test>perl -Mstrict -w
package x;

sub f{ 1 }

42;
^Z
Useless use of a constant in void context at - line 5.

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Although it is returned and checked at runtime; at the point of parsing it is in a void context.

And you can't avoid that by prefixing a return statement either:

C:\test>perl -Mstrict -w
package x;
sub f{ 1 }
return 42;
^Z
Can't return outside a subroutine at - line 3.

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Re^4: warnings pragma anomaly
by choroba (Cardinal) on Oct 19, 2015 at 22:25 UTC
    I usually don't run modules, I use them. No warning is produced in such situations.
    لսႽ† ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ
[reply]

      True. But before we even start talking about unit tests, it would be nice to have 

      perl -wc Foo.pm

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      at least come up with the "Foo.pm syntax ok" message and without raising any warnings.

      Given 

      package Foo;
42;

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      this would give "syntax ok" but also the "useless use of constant in void context" warning, whereas 
      package Foo;
1;

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      would only give the "syntax ok" message.

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[d/l]
[select]
        You can still do 
        perl -MFoo -wce1

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        لսႽ† ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ
[reply]
[d/l]

      Good point :)

[reply]

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