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Iterator version 0.03
=====================
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.
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
Test::Simple
COPYRIGHT AND LICENSE
Eric J. Roode, roode@cpan.org
To avoid my spam filter, please include "Perl", "module", or this
module's name in the message's subject line, and/or GPG-sign your
message.
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.
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