in reply to Re^2: Tiny Perl puzzle
in thread Tiny Perl puzzle

I think B::Deparse gets it wrong -- as it sometimes does -- when you add -p:

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This is confirmed by the more low-level output of B::Concise:

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Dave

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Re^4: Tiny Perl puzzle
by Anonymous Monk on Jun 07, 2014 at 07:25 UTC

    Look at the way Deparse uses whitespace, its subtle

    My theory: When Deparse tries to add parens wherever it can, it treats the first two as a function call (which was my first guess too). But as tobyink correctly surmised, that first two is treated by print as a filehandle.

    That is not the way I read it :) Usually, Deparse doesn't add extraneous space to function calls, its always "foo( ... )" its never "foo ( ... )"

    so the way I read that deparse output is as filehandle not function call

    For example 

    $ perl -MO=Deparse 2
sub two {
    rand;
}
print two(two() == 'five' ? 'true' : 'false');
2 syntax OK

$ perl -MO=Deparse,-p 2
sub two {
    (rand);
}
print(two(((two() == 'five') ? 'true' : 'false')));
2 syntax OK

    [download]

    When I look at Re^2: Tiny Perl puzzle I see  print( filehandle ... );

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Re^4: Tiny Perl puzzle
by LanX (Saint) on Jun 07, 2014 at 15:38 UTC
    I don't think so.

    did you recompile the output?

    I can't test ATM, but most likely it depends if a function is known at compile time. Contrary to AnoMonk I doubt space matters.

    Anyway IMHO the indirect object syntax should be deprecated....

    Cheers Rolf

    (addicted to the Perl Programming Language)

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      I can't test ATM

      You gotta stop saying that :)

      Contrary to AnoMonk I doubt space matters.

      Sure it does, it matters how Deparse places the space, because it matters to perl

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      That is exactly as deparsed with -p, behaves exactly like the original
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        > Sure it does, it matters how Deparse places the space, because it matters to perl

        it depends! ;-)

        > > most likely it depends if a function is known at compile time

        > perl
open ONE, ">", "/tmp/tst";

sub ONE { "@_ \n Space doesn't matter! \n" }

print ONE ( TWO );          # sub-call

__END__
TWO 
 Space doesn't matter!

        [download]

        update

        ALSO:

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        BUT:

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        Cheers Rolf

        (addicted to the Perl Programming Language)

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