Re^2: Perl oddities

[Roy Johnson]

It seems pretty sensible to me to say that the integer portion of -3.5 is -3.

It's still pretty easy to write ceil and floor:

sub ceil {
  my $n = shift;
  int($n) + ($n > int($n));
}

sub floor {
  my $n = shift;
  int($n) - ($n < int($n));
}

[merlyn]

There's no promise in the docs that less than and greater than return 1 and 0. Just "true" and "false". It could return 37 for true, and undef for false.

[TimToady]

We will try to nail those down a little better in Perl 6. Returning the null string for false was a premature optimization on my part, and a false economy (as it were), so the standard boolean operators will return 0 and 1 in Perl 6 so that when you print them out, they look like something rather than nothing. Also, since Perl 6 distinguishes boolean from numeric and string contexts, it can optimize away the actual production of a 0 or 1 value in many cases.

That's not to say that we're ever going to require people to use 0 and 1 for boolean values. Perl 6 will be just like Perl 5 in letting you treat just about anything as a boolean value. So non-zero numbers are still true, as are strings that aren't null or "0". And maybe we can fix the "0" problem too.

[Roy Johnson]

As someone who has just posted a couple of times about undocumented behavior, I will not protest too loudly about being called on this one. Still, it's a convention that has been relied on and seems unlikely to change.

The obvious fix is:

sub ceil {
  my $n = shift;
  int($n) + ($n > int($n) ? 1 : 0);
}