On 01/25/2016 05:13 PM, lee wrote:
Paul Johnson <p...@pjcj.net> writes:
On Mon, Jan 25, 2016 at 12:24:04AM +0100, lee wrote:
Paul Johnson <p...@pjcj.net> writes:
[...]
Consider with these examples that an expression like (1, 3) might
unexpectedly evaluate to 3, and you start to think that you don't like
things like
sub s {
my $a = 1;
my $b = 3;
return ($a, $b);
}
anymore because you could, by mistake (or intentionally), write
my $x = s;
. So let me re-phrase my original question to: How do you /safely/
return arrays?
That means I need an error message for '$x = s;' because I'd write that
only by mistake.
You could add to your subroutine:
die "Only call in list context" unless wantarray;
Oh, that's really cool :)
IMHO, this is pretty cool too:
return wantarray() ? ($a, $b) : [$a, $b];
In a list context, you get back a list.. otherwise you get back a
reference to a list. Might not be what you want, though.
Works with arrays, too..
my @anarray = (....)
return wantarray() ? (@anarray) : [@anarray];
Nathan
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