Quick quiz: What is the output from the following program? 
#!/usr/bin/perl -w

use strict;

sub foo($) {
        print "$_[0]\n";
}

my $foo = 'foo';
my @foo = ($foo);

foo($foo);
foo(@foo);
foo($foo[0]);

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If you figured there was no difference, you're in for a surprise. With a regular subroutine, this is what happens, but prototype declaration makes things quite different.

Although it makes sense in a strange kind of way, why can't @foo be treated as an implicit list for DWIM purposes?

In reply to Function Prototype Context Conversion by tadman

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