Re: Problems with map(function, array)

Nothing to do with map really. uc has magic!

In the following construct, uc is getting called with no parameters:

my @caps = map uc, @lower;
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As per perlfunc, when called with no parameters, uc operates on $_. So you need to make your function act the same (as indeed you did in your second experiment).

From Perl 5.10 and above, there's a better technique to write such functions:

sub my_uc (_) {  # note underscore in parentheses
  my $c = shift;
  return uc($c);
}
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And now my_uc has the same magic as uc.

perl -E'sub Monkey::do{say$_,for@_,do{($monkey=[caller(0)]->[3])=~s{::}{ }and$monkey}}"Monkey say"->Monkey::do'

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Re^2: Problems with map(function, array) by Redei (Initiate) on Dec 12, 2012 at 14:06 UTC
Thank you very much. That is just what I needed. Now, instead of `sub twice { 2 * (shift // $_) }` I'll use something like `sub twice(_) { 2 * shift }`	[reply] [d/l] [select]