broquaint's recent reply to a discussion on programming style, has set me thinking.

So, if you want modifiable scalar parameters, you can change them inside a sub by using $_[0], $_[1] etc. as lvalues without resorting to references. Interesting.

Also, I am reminded of how $_ gets bound to successive members of an array: 


foreach (@foo) {
    $_++;        # Add 1 to each member of @foo
}

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Is the same true if you use an intermediate variable - does it get aliased, or merely assigned? Apologies: I don't have access to a machine running Perl at the moment

foreach my $bar (@foo) {
    $bar++;
}

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Also I'm wondering about the future of all this. What of behaviour in Perl 6? Coming back to the first scenario, I hear that Perl 6 will be getting some Ruby features. Does this include passing parameters by name and hence Jensen's device?

--rW

Note: magicality - this might be a new term I am coining. Magicality bears as much relation to magic as sexuality does to sex.

In reply to Thoughts on the magicality of @_ and $_ by rinceWind

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