On 01.10.2013 08:10, perl-diddler@tlinx.org via RT wrote:
Show quoted text> <URL:
https://rt.cpan.org/Ticket/Display.html?id=89054 >
>
> On Mon Sep 30 07:52:18 2013, l.mai@web.de wrote:
>> Line 181 of P.pm is:
>>
>> 1;}
>>
>> This '1;' does nothing and can be removed.
> ----
> This is the last line of "package P". package main continues after that. when one does a "use packagename", I was under the impression that, generally speaking, it needs to return a "true" value. Thus it has 1; as the last line of the package definition.
>
> I understand that with P included in a file with another package that the end value isn't used, however, I try to develop my packages to be ready for separation without requiring source changes. That was an issue on p5p some time back that I eventually solved with the "use mem" pragma that allows a module to be used directly from its "in-mem"[ory] version.
>
> With that in place, and the 1 at the end of the package, it should be fairly trivial to split a package to a separate file if desired -- thus I always try to put a 1; at the end of package definitions.
>
> Unless it is causing a problem, it isn't really random and does serve my purposes, so I'd rather not remove it needlessly.
>
> Is it causing some problem?
It's not causing problems but to me it indicates the author doesn't
really understand use/require. The "1;" doesn't end a *package*; it's
the return value of the *file*. (For some reason it's customary to leave
out 'return' in modules, though.)
Example:
===Foo.pm====
{
package Foo;
...
}
{
package Bar;
...
}
return 1;
__END__
This can be loaded with 'use Foo' because it's in the file Foo.pm and
returns a true value. Note that file loading doesn't care about
packages, only files.
===Foo2.pm====
{
package Foo;
...
}
{
package Bar;
...
}
1;
__END__
^ Same thing, but this time we use an implicit return value (last
expression evaluated in the file).
Ultimately it's a style issue. Personally I prefer "1;" (or "'ok';") at
the end of the file because in my mind it's part of the file loading
system, not any package. If you disagree, feel free to close this bug.
--
Lukas Mai <l.mai@web.de>
RT for rt.cpan.org