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sub swap { my ($a, $b) = \(@_); ( $$a, $$b ) = ( $$b, $$a ); } my ($x,$y)=(42,666); $\="\n"; print "($x,$y)"; #> (42,666) swap($x,$y); print "($x,$y)"; #> (666,42)
is that idea new?


for completeness, this works too:

sub swap { my $a = \shift; my $b = \shift; ( $$a, $$b ) = ( $$b, $$a ); }

Cheers Rolf

UPDATE: I was asked if this example accomplishes anything that the following doesn't:
sub swap { ($_[0], $_[1] ) = ( $_[1], $_[0] ); }
no it doesn't ) I just wanted to meditate about a pattern to have named aliases.

Compare PBP's critic about using unreadable variables like $_[0].

of course swap() is too short to profit from named arguments.

) except by not dieing on literals.

In reply to RFC: Idiom for named read-write arguments (aliases) instead of using $_[0] etc by LanX

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