# $Id: Set.pm,v 1.2 2006/01/14 00:44:37 martin Exp $## Copyright 2005 Nature Publishing Group# This program is free software; you can redistribute it and/or# modify it under the terms of the GNU General Public License# as published by the Free Software Foundation; either version 2# of the License, or (at your option) any later version.## This file provides an object-friendly version of Set::Arraypackage Bibliotech::DBI::Set;use strict;use base 'Set::Array';use Want;# make count return how many entries there aresub count {  shift->length;}sub flatten_helper {  my @ret;  foreach (@_) {    push @ret, (ref($_) eq 'ARRAY' ? flatten_helper(@{$_}) : $_);  }  return @ret;}# object-friendlysub flatten{   my($self) = @_;   if( want('OBJECT') ){     return $self->new(flatten_helper(@{$self}));   }   if( !defined wantarray ){     @{$self} = flatten_helper(@{$self});      return $self   }   my @temp = flatten_helper(@{$self});   if(wantarray){ return @temp }   if(defined wantarray){ return \@temp }}# object-friendly, plus preserve ordersub unique {  my ($set) = @_;  my $new_set = ref($set)->new;  my %seen;  foreach (@{$set}) {    CORE::push(@{$new_set}, $_)  # preserving order	unless $seen{$_}++;  }  if (want('OBJECT')) {    return $new_set;  }  if ( !(defined wantarray) ) {    @{$set} = @{$new_set};    return $set;  }  return @{$new_set} if wantarray;  return $new_set;}# object-friendlysub difference{   my($op1, $op2, $reversed) = @_;   ($op2,$op1) = ($op1,$op2) if $reversed;   my(%item1,%item2,@diff);   CORE::foreach(@$op2){ $item2{$_}++ }   CORE::foreach(@$op1){     next if $item1{$_}++;     next if $item2{$_};     CORE::push(@diff,$_);   }	   if(want('OBJECT') || !(defined wantarray)){      @$op1 = @diff;      return $op1;   }   if(wantarray){ return @diff }   if(defined wantarray){ return \@diff }}# intersection() is already object-friendly# object-friendlysub symmetric_difference{   my($op1, $op2, $reversed) = @_;   ($op2,$op1) = ($op1,$op2) if $reversed;   my(%count1,%count2,%count3,@symdiff);   @count1{@$op1} = @$op1;   @count2{@$op2} = @$op2;   CORE::foreach(CORE::keys %count1){     $count3{$_} ||= [];     my $c = $count3{$_};     $c->[0]++;     $c->[1] = $count1{$_};   }   CORE::foreach(CORE::keys %count2){     $count3{$_} ||= [];     my $c = $count3{$_};     $c->[0]++;     $c->[1] = $count2{$_};   }   if(want('OBJECT') || !(defined wantarray)){      @$op1 = CORE::map{$count3{$_}->[1]} CORE::grep{$count3{$_}->[0] == 1} CORE::keys %count3;      return $op1;   }   @symdiff = CORE::map{$count3{$_}->[1]} CORE::grep{$count3{$_}->[0] == 1} CORE::keys %count3;   if(wantarray){ return @symdiff }   if(defined wantarray){ return \@symdiff }}# object-friendlysub union{   my($op1, $op2, $reversed) = @_;   ($op2,$op1) = ($op1,$op2) if $reversed;   my %union;   CORE::foreach(@$op1, @$op2){     $union{$_} ||= [];     my $u = $union{$_};     $u->[0]++;     $u->[1] = $_;   }   if(want('OBJECT') || !(defined wantarray)){      @$op1 = CORE::map{$union{$_}->[1]} CORE::keys %union;      return $op1;   }   my @union = CORE::map{$union{$_}->[1]} CORE::keys %union;   if(wantarray){ return @union }   if(defined wantarray){ return \@union }}sub first {  shift->shift;  # ;-)}sub next {  shift->shift;  # ;-)}sub output_line {  my ($self, $func, $prefix) = @_;  return $prefix || '', join(', ', map($_->$func, @$self)), "\n";}# support Bibliotech::DBI::Set object being used in FOREACH directive of Template Toolkit# as it is within Bibliotech::WebAPI::Action::Tags::Get for answer->listsub as_list {  # simply by having as_list() defined, Template::Iterator now interprets this differently, as an arrayref  shift;}package Bibliotech::DBI::Set::Line;use strict;use overload    '""' => sub { shift->stringify_self; },    bool => sub { shift->stringify_self ? 1 : 0; },    fallback => 1;sub stringify_self {  shift->[0];}1;__END__