in reply to Tiny Perl puzzle

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Can't test ATM :)

Cheers Rolf

(addicted to the Perl Programming Language)

update

tobyinc's analysis is correct! :)

one more reason to enforce use strict and 'warnings'...

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Re^2: Tiny Perl puzzle
by Anonymous Monk on Jun 06, 2014 at 01:16 UTC
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      I think B::Deparse gets it wrong -- as it sometimes does -- when you add -p:

      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.

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

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      Dave

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        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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