It's the exact difference between the following two code snippets:

  BEGIN {
    my $var = 10;
    sub next {
      return ++$var;
    }
  }

[download]

And the following:

  sub next {
    state $var = 10;
    return ++$var;
  }

[download]

Now let's have a show of hands, how many people prefer the First Way To Do It? ... hmm, I see no hands? I thought as much :)

Tip o' the hat to Roy Johnson for pointing out that it was a BEGIN block I wanted, not an lexical scope with a label BEGIN:. And you do need a BEGIN block, not a bare block, otherwise you can run into grief with uninitialised values (which is kind of the whole point).

• another intruder with the mooring in the heart of the Perl

In reply to Re^2: Bring Out Your New Perl Code by grinder
in thread Bring Out Your New Perl Code by Limbic~Region

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