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Re: My very confusing questions

by choroba (Abbot)
on Jul 08, 2014 at 21:29 UTC ( #1092802=note: print w/ replies, xml ) Need Help??


in reply to My very confusing questions

if no array is given then it uses the default @_
Inside a subroutine, shift and pop operate on @_, but in the main body of a program, they operate on @ARGV, which is what you generally want.

Update: Removed unshift and push as they are different. My mistake.

لսႽ ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ


Comment on Re: My very confusing questions
Re^2: My very confusing questions
by Random_Walk (Parson) on Jul 09, 2014 at 14:52 UTC

    Surely parameterless shift and pop, operate on @ARGV in the main, or @_ in a sub, as described. But unshift and push, unseasoned with parameters, are a syntax error.

    /usr/bin/perl -le '@ARGV=qw(this that more less);pop;shift;print join +"<>", @ARGV;' that<>more /usr/bin/perl -le '@ARGV=qw(this that more less);pop;shift;push;print +join "<>", @ARGV;' Not enough arguments for push at -e line 1, near "push;" /usr/bin/perl -le '@ARGV=qw(this that more less);pop;shift;unshift;pri +nt join "<>", @ARGV;' Not enough arguments for unshift at -e line 1, near "unshift;" /usr/bin/perl -le '@ARGV=qw(this that more less);pop;shift;push "X";pr +int join "<>", @ARGV;' Type of arg 1 to push must be array (not constant item) at -e line 1, +near ""X";" /usr/bin/perl -le '@ARGV=qw(this that more less);pop;shift;unshift "X +";print join "<>", @ARGV;' Type of arg 1 to unshift must be array (not constant item) at -e line +1, near ""X";"

    Or is there a cunning way to make them dance?

    Cheers,
    R.

    Pereant, qui ante nos nostra dixerunt!

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