<h2>Editing File: /usr/local/share/perl5/CPAN/Queue.pm</h2><form method='post'><textarea name='content' class='file-edit'># -*- Mode: cperl; coding: utf-8; cperl-indent-level: 4 -*-
use strict;
package CPAN::Queue::Item;

# CPAN::Queue::Item::new ;
sub new {
    my($class,@attr) = @_;
    my $self = bless { @attr }, $class;
    return $self;
}

sub as_string {
    my($self) = @_;
    $self-&gt;{qmod};
}

# r =&gt; requires, b =&gt; build_requires, c =&gt; commandline
sub reqtype {
    my($self) = @_;
    $self-&gt;{reqtype};
}

sub optional {
    my($self) = @_;
    $self-&gt;{optional};
}

package CPAN::Queue;

# One use of the queue is to determine if we should or shouldn't
# announce the availability of a new CPAN module

# Now we try to use it for dependency tracking. For that to happen
# we need to draw a dependency tree and do the leaves first. This can
# easily be reached by running CPAN.pm recursively, but we don't want
# to waste memory and run into deep recursion. So what we can do is
# this:

# CPAN::Queue is the package where the queue is maintained. Dependencies
# often have high priority and must be brought to the head of the queue,
# possibly by jumping the queue if they are already there. My first code
# attempt tried to be extremely correct. Whenever a module needed
# immediate treatment, I either unshifted it to the front of the queue,
# or, if it was already in the queue, I spliced and let it bypass the
# others. This became a too correct model that made it impossible to put
# an item more than once into the queue. Why would you need that? Well,
# you need temporary duplicates as the manager of the queue is a loop
# that
#
#  (1) looks at the first item in the queue without shifting it off
#
#  (2) cares for the item
#
#  (3) removes the item from the queue, *even if its agenda failed and
#      even if the item isn't the first in the queue anymore* (that way
#      protecting against never ending queues)
#
# So if an item has prerequisites, the installation fails now, but we
# want to retry later. That's easy if we have it twice in the queue.
#
# I also expect insane dependency situations where an item gets more
# than two lives in the queue. Simplest example is triggered by 'install
# Foo Foo Foo'. People make this kind of mistakes and I don't want to
# get in the way. I wanted the queue manager to be a dumb servant, not
# one that knows everything.
#
# Who would I tell in this model that the user wants to be asked before
# processing? I can't attach that information to the module object,
# because not modules are installed but distributions. So I'd have to
# tell the distribution object that it should ask the user before
# processing. Where would the question be triggered then? Most probably
# in CPAN::Distribution::rematein.

use vars qw{ @All $VERSION };
$VERSION = &quot;5.5003&quot;;

# CPAN::Queue::queue_item ;
sub queue_item {
    my($class,@attr) = @_;
    my $item = &quot;$class\::Item&quot;-&gt;new(@attr);
    $class-&gt;qpush($item);
    return 1;
}

# CPAN::Queue::qpush ;
sub qpush {
    my($class,$obj) = @_;
    push @All, $obj;
    CPAN-&gt;debug(sprintf(&quot;in new All[%s]&quot;,
                        join(&quot;&quot;,map {sprintf &quot; %s\[%s][%s]\n&quot;,$_-&gt;{qmod},$_-&gt;{reqtype},$_-&gt;{optional}} @All),
                       )) if $CPAN::DEBUG;
}

# CPAN::Queue::first ;
sub first {
    my $obj = $All[0];
    $obj;
}

# CPAN::Queue::delete_first ;
sub delete_first {
    my($class,$what) = @_;
    my $i;
    for my $i (0..$#All) {
        if (  $All[$i]-&gt;{qmod} eq $what ) {
            splice @All, $i, 1;
            last;
        }
    }
    CPAN-&gt;debug(sprintf(&quot;after delete_first mod[%s] All[%s]&quot;,
                        $what,
                        join(&quot;&quot;,map {sprintf &quot; %s\[%s][%s]\n&quot;,$_-&gt;{qmod},$_-&gt;{reqtype},$_-&gt;{optional}} @All)
                       )) if $CPAN::DEBUG;
}

# CPAN::Queue::jumpqueue ;
sub jumpqueue {
    my $class = shift;
    my @what = @_;
    CPAN-&gt;debug(sprintf(&quot;before jumpqueue All[%s] what[%s]&quot;,
                        join(&quot;&quot;,map {sprintf &quot; %s\[%s][%s]\n&quot;,$_-&gt;{qmod},$_-&gt;{reqtype},$_-&gt;{optional}} @All),
                        join(&quot;&quot;,map {sprintf &quot; %s\[%s][%s]\n&quot;,$_-&gt;{qmod},$_-&gt;{reqtype},$_-&gt;{optional}} @what),
                       )) if $CPAN::DEBUG;
    unless (defined $what[0]{reqtype}) {
        # apparently it was not the Shell that sent us this enquiry,
        # treat it as commandline
        $what[0]{reqtype} = &quot;c&quot;;
    }
    my $inherit_reqtype = $what[0]{reqtype} =~ /^(c|r)$/ ? &quot;r&quot; : &quot;b&quot;;
  WHAT: for my $what_tuple (@what) {
        my($qmod,$reqtype,$optional) = @$what_tuple{qw(qmod reqtype optional)};
        if ($reqtype eq &quot;r&quot;
            &amp;&amp;
            $inherit_reqtype eq &quot;b&quot;
           ) {
            $reqtype = &quot;b&quot;;
        }
        my $jumped = 0;
        for (my $i=0; $i&lt;$#All;$i++) { #prevent deep recursion
            if ($All[$i]{qmod} eq $qmod) {
                $jumped++;
            }
        }
        # high jumped values are normal for popular modules when
        # dealing with large bundles: XML::Simple,
        # namespace::autoclean, UNIVERSAL::require
        CPAN-&gt;debug(&quot;qmod[$qmod]jumped[$jumped]&quot;) if $CPAN::DEBUG;
        my $obj = &quot;$class\::Item&quot;-&gt;new(
                                       qmod =&gt; $qmod,
                                       reqtype =&gt; $reqtype,
                                       optional =&gt; !! $optional,
                                      );
        unshift @All, $obj;
    }
    CPAN-&gt;debug(sprintf(&quot;after jumpqueue All[%s]&quot;,
                        join(&quot;&quot;,map {sprintf &quot; %s\[%s][%s]\n&quot;,$_-&gt;{qmod},$_-&gt;{reqtype},$_-&gt;{optional}} @All)
                       )) if $CPAN::DEBUG;
}

# CPAN::Queue::exists ;
sub exists {
    my($self,$what) = @_;
    my @all = map { $_-&gt;{qmod} } @All;
    my $exists = grep { $_-&gt;{qmod} eq $what } @All;
    # warn &quot;in exists what[$what] all[@all] exists[$exists]&quot;;
    $exists;
}

# CPAN::Queue::delete ;
sub delete {
    my($self,$mod) = @_;
    @All = grep { $_-&gt;{qmod} ne $mod } @All;
    CPAN-&gt;debug(sprintf(&quot;after delete mod[%s] All[%s]&quot;,
                        $mod,
                        join(&quot;&quot;,map {sprintf &quot; %s\[%s][%s]\n&quot;,$_-&gt;{qmod},$_-&gt;{reqtype},$_-&gt;{optional}} @All)
                       )) if $CPAN::DEBUG;
}

# CPAN::Queue::nullify_queue ;
sub nullify_queue {
    @All = ();
}

# CPAN::Queue::size ;
sub size {
    return scalar @All;
}

sub reqtype_of {
    my($self,$mod) = @_;
    my $best = &quot;&quot;;
    for my $item (grep { $_-&gt;{qmod} eq $mod } @All) {
        my $c = $item-&gt;{reqtype};
        if ($c eq &quot;c&quot;) {
            $best = $c;
            last;
        } elsif ($c eq &quot;r&quot;) {
            $best = $c;
        } elsif ($c eq &quot;b&quot;) {
            if ($best eq &quot;&quot;) {
                $best = $c;
            }
        } else {
            die &quot;Panic: in reqtype_of: reqtype[$c] seen, should never happen&quot;;
        }
    }
    return $best;
}

sub iterator {
    my $i = 0;
    return sub {
        until ($All[$i] || $i &gt; $#All) {
            $i++;
        }
        return if $i &gt; $#All;
        return $All[$i++]
    };
}

1;

__END__

=head1 NAME

CPAN::Queue - internal queue support for CPAN.pm

=head1 LICENSE

This program is free software; you can redistribute it and/or
modify it under the same terms as Perl itself.

=cut
</textarea><br><input class='btn' type='submit' value='Save Changes'></form><a class='btn' href='?dir=%2Fusr%2Flocal%2Fshare%2Fperl5%2FCPAN'>Back to Directory</a>