NAME

PerlX::Range - Lazy Range object in Perl 5

SYNOPSIS

  use PerlX::MethodCallWithBlock;
  use PerlX::Range;

  my $a = 1..5000;

  $a->each {
      # $_ is the current value

      return 0 if should_break($_);
  };

DESCRIPTION

PerlX::Range is an attemp to implement make range operator lazy. When you say:

    my $a = 1..10;

This `$a` variable is then now a PerlX::Range object.

At this point the begin of range can only be a constant, and better only be a number literal.

The end of the range can be a number, or a asterisk *, which means "whatever", or Inf. This syntax is stolen from Perl6.

After the end of range, it optionally take a :by(N) modifier, where N can be a number literal. This syntax is also stolen from Perl6.

Therefore, this is how you represent all odd numbers:

    my $odd = 1..*:by(2);

METHODS

min, from, first

Retrieve the minimum value of the range.

max, to, last

Retrieve the maximum value of the range.

each($cb)

Iterate over the range one by one, the $cb should be a code ref. Inside the body of that, $_ refers to the current value.

If you want to stop before it reach the end of the range, or you have to because the range is infinite, you need to say return 0. A defined false value from $cb will make the iteration stop.

AUTHOR

Kang-min Liu <gugod@gugod.org>

SEE ALSO

LICENSE AND COPYRIGHT

Copyright (c) 2009, Kang-min Liu <gugod@gugod.org>.

This is free software, licensed under:

    The MIT (X11) License

DISCLAIMER OF WARRANTY

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