Pass sub reference

vit has asked for the wisdom of the Perl Monks concerning the following question:

Dear Monks,
I have a sub described explicitly like

sub xxx
{
my $x1 = shift;
my $x2 = shift;
print "$x1, $x2\n";
}
[download]

I need to pass it into sub yyy and call it from there.
What's the right way to do this? Something like

..............
yyy( <xxx("hi", "i am here")> )
..............

sub yyy
{
<reference to xxx> = shift;
..........
call <xxx>;
}
[download]

Comment on Pass sub reference Select or Download Code

Replies are listed 'Best First'.
Re: Pass sub reference by Anonymous Monk on Oct 28, 2010 at 17:04 UTC
For example: `#!/usr/bin/perl sub xxx { my $x1 = shift; my $x2 = shift; print "$x1, $x2\n"; } sub yyy { my $func = shift; $func->(@_) } yyy( \&xxx, "foo", 42 ); # \&xxx is the sub reference.` [download]	[reply] [d/l]
Re^2: Pass sub reference by Anonymous Monk on Oct 28, 2010 at 17:16 UTC
...or maybe, if you want to pass around the arguments together with the function, you can wrap the call in another sub: `... sub yyy { my $func = shift; $func->(); } yyy( sub { xxx("foo", 42) } );` [download]	[reply] [d/l]
Re^3: Pass sub reference by AnomalousMonk (Archbishop) on Oct 29, 2010 at 00:59 UTC
Which is to say (warning: semi-advanced topic, but not really all that scary): Use a closure. See tutorial Closure on Closures.	[reply]