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=head1 NAME |
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|
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Coro::Cont - schmorp's faked continuations |
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|
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=head1 SYNOPSIS |
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|
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use Coro::Cont; |
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|
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# multiply all hash keys by 2 |
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my $cont = csub { |
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result $_*2; |
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result $_; |
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}; |
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my %hash2 = map &$csub, &hash1; |
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|
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# dasselbe in grün (as we germans say) |
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sub mul2 : Cont { |
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result $_*2; |
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result $_; |
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} |
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|
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my %hash2 = map mul2, &hash1; |
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|
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|
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=head1 DESCRIPTION |
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|
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=over 4 |
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|
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=cut |
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|
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package Coro::Cont; |
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|
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use Coro::State; |
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use Coro::Specific; |
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|
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use base 'Exporter'; |
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|
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$VERSION = 0.08; |
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@EXPORT = qw(csub result); |
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|
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{ |
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use subs 'csub'; |
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|
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my @csub; |
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|
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# this way of handling attributes simply is NOT scalable ;() |
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sub import { |
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Coro::Cont->export_to_level(1, @_); |
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my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE}; |
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no warnings; |
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*{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"} = sub { |
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my ($package, $ref) = (shift, shift); |
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my @attrs; |
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for (@_) { |
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if ($_ eq "Cont") { |
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push @csub, $ref; |
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} else { |
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push @attrs, $_; |
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} |
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} |
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return $old ? $old->($package, $ref, @attrs) : @attrs; |
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}; |
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} |
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|
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sub INIT { |
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for (@csub) { |
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$$_ = csub $$_; |
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} |
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@csub = (); |
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} |
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} |
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|
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=item csub { ... } |
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|
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Create a new "continuation" (when the sub falls of the end it is being |
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terminated). |
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|
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=cut |
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|
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our $curr = new Coro::Specific; |
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our @result; |
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|
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sub csub(&) { |
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my $code = $_[0]; |
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my $coro = new Coro::State sub { &$code while 1 }; |
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my $prev = new Coro::State; |
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sub { |
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push @$$curr, [$coro, $prev]; |
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&Coro::State::transfer($prev, $coro, 0); |
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wantarray ? @{pop @result} : ${pop @result}[0]; |
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}; |
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} |
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|
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=item result [list] |
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|
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Return the given list/scalar as result of the continuation. |
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|
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=cut |
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|
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sub result { |
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push @result, [@_]; |
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&Coro::State::transfer(@{pop @$$curr}, 0); |
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@_; |
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} |
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|
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1; |
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|
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=back |
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|
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=head1 AUTHOR |
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|
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Marc Lehmann <pcg@goof.com> |
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http://www.goof.com/pcg/marc/ |
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|
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=cut |
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|
