According to Benchmark the first form is very slightly faster, but probably not enough to make much of a difference. 
use Benchmark qw/cmpthese/;

sub s1 {my ($arg1, $arg2, $arg3) = @_;}; 
sub s2 { my $arg1 = shift; my $arg2 = shift; my $arg3 = shift; }

cmpthese(200000, {
shift  => ' { s2(1,2,3) }',
list  => ' {s1(1,2,3)}',
})


Benchmark: timing 200000 iterations of list, shift...
      list:  3 wallclock secs ( 2.14 usr +  0.01 sys =  2.15 CPU) @ 93
+023.26/s (n=200000)
     shift:  2 wallclock secs ( 2.25 usr +  0.02 sys =  2.27 CPU) @ 88
+105.73/s (n=200000)
         Rate shift  list
shift 88106/s    --   -5%
list  93023/s    6%    --

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In reply to Re: Silly question about function args by Paladin
in thread Silly question about function args by Anonymous Monk

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