Re^2: Using 'Shift' in subroutine argument

If you execute this

use strict;
use warnings;
one(1,2,3,4);
sub one{
    &two (shift, shift);
}
sub two
{
    print "Elements : \n @_ \n";
}
[download]

you would get

Elements :
 1 2
[download]

Which means that it's same as passing the first two elements of the list the sub-routine one has received.Though I was not able to compile the code

sub one{
    &two shift, shift;
}
[download]

which is your case.Provide the some context of your snippet that would help everyone to learn.

The world is so big for any individual to conquer

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Re^3: Using 'Shift' in subroutine argument by shmem (Chancellor) on Nov 02, 2007 at 13:20 UTC
Though I was not able to compile the code `sub one{ &two shift, shift; }` [download] That's a syntax error. Subroutine invocations with & require parens. Drop the ampersand and move the `sub two` definition up: `use strict; use warnings; one(1,2,3,4); sub two { print "Elements : \n @_ \n"; } sub one { two shift, shift; }` [download] To resolve the bareword `two` as a subroutine call (in `two shift, shift`), the compiler needs to have seen the sub declaration already. Alternative: `use strict; use warnings; sub two; # forward declaration one(1,2,3,4); sub one { two shift, shift; } sub two { print "Elements : \n @_ \n"; }` [download] --shmem _($_=" "x(1<<5)."?\n".q·/)Oo. G°\ / /\_¯/(q / ---------------------------- \__(m.====·.(_("always off the crowd"))."· ");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}	[reply] [d/l] [select]

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Re^3: Using 'Shift' in subroutine argument
by shmem (Chancellor) on Nov 02, 2007 at 13:20 UTC

Though I was not able to compile the code
sub one{
    &two shift, shift;
}
[download]

That's a syntax error. Subroutine invocations with & require parens.

Drop the ampersand and move the sub two definition up:

use strict;
use warnings;
one(1,2,3,4);
sub two {
    print "Elements : \n @_ \n";
}
sub one {
    two shift, shift;
}
[download]

To resolve the bareword two as a subroutine call (in two shift, shift), the compiler needs to have seen the sub declaration already. Alternative:

use strict;
use warnings;
sub two;      # forward declaration
one(1,2,3,4);
sub one {
    two shift, shift;
}
sub two {
    print "Elements : \n @_ \n";
}
[download]

--shmem

_($_=" "x(1<<5)."?\n".q·/)Oo.  G°\        /
                              /\_¯/(q    /
----------------------------  \__(m.====·.(_("always off the crowd"))."·
");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}

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