Iterator version 0.01
=====================

This module is meant to be the definitive implementation of iterators,
as popularized by Mark Jason Dominus's lectures and recent book
(_Higher Order Perl_, Morgan Kauffman, 2005).

An "iterator" is an object, represented as a code block that generates
the "next value" of a sequence, and generally implemented as a
closure.  Iterator.pm provides a class that simplifies creation and
use of these iterator objects, and provides many general-purpose
iterator functions.

EXAMPLES

Synopsis:

    $it = Iterator->new( sub { some code } );

Simple "upto" counter (Dominus, p. 121):

    sub upto
    {
        my ($m, $n) = @_;

        return Iterator->new( sub {
            return $m++  if $m <= $n;
            Iterator::X::Am_Now_Exhausted->throw();
        });
    }

    my $it = upto (3, 5);

    $i = $it->value;     #  returns 3
    $i = $it->value;     #  returns 4
    $i = $it->value;     #  returns 5
    $i = $it->value;     #  throws an Iterator::X::Exhausted exception.

    $another_it = upto (7, 10);
    while ($another_it->isnt_exhausted)
    {
        print $another_it->value, "\n";
    }
    # The above prints 7, 8, 9, 10 and throws no exceptions.
    # Another call to $another_it->value would throw an exception.

DEVELOPMENT STATE

This is a brand-new module.  It has a decent test suite, but has
not been extensively field-tested.  Therefore, it should be considered
"beta" software, and used with care.

If you find any bugs, or if any behavior of Iterator surprises you,
I would be grateful if you could send me an email message about it.
Thanks.


INSTALLATION

To install this module, do the standard Perl module four-step:

   perl Makefile.PL    or    perl Makefile.pl LIB='my/install/path'
   make
   make test
   make install

DEPENDENCIES

This module requires these other modules and libraries:

  Exception::Class

COPYRIGHT AND LICENSE

Eric J. Roode, roode@cpan.org

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Copyright (c) 2005 by Eric J. Roode. All Rights Reserved.
This module is free software; you can redistribute it and/or modify it
under the same terms as Perl itself.
