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in reply to Re: simple anonymous subroutine and variable interpolation timing question
in thread simple anonymous subroutine and variable interpolation timing question

I was considering the closure with a local variable, but I was wondering if there was some sneaky way the experts did it. I don't like the looks of the eval method, so I think I'll stick with the first.

Thanks as always Ikegami!

  • Comment on Re^2: simple anonymous subroutine and variable interpolation timing question

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Re^3: simple anonymous subroutine and variable interpolation timing question
by ikegami (Patriarch) on Jun 23, 2011 at 21:24 UTC

    You don't have to create a separate sub. Alternatives: 

    my $sub = sub { my ($str) = @_; sub { $str } }->($str);

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    my $sub = sub { my $str = $str; sub { $str } }->();

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    my $sub = do { my $str = $str; sub { $str } };

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    my $str_copy = $str;
my $sub = sub { $str_copy };

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    In practice, it's usually a non-issue since you either have a variable that doesn't change to begin with 

    for my $str (...) {
   ... sub { ... $str ... } ...
}

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    or you want to factor out the code to a sub anyway. 
    sub make_list_iterator { 
   my @list = @_;
   return sub {
      return @list ? shift(@list) : ();
   };
}

my $iter = make_list_iterator(@list);

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Re^3: simple anonymous subroutine and variable interpolation timing question
by tj_thompson (Monk) on Jun 23, 2011 at 21:27 UTC
    errr, meant lexical variable, not local.
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