Revision f4d0b637
Von Moritz Bunkus vor fast 16 Jahren hinzugefügt
| doc/modules/LICENSE.List-MoreUtils | ||
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COPYRIGHT AND LICENSE
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Copyright (C) 2004-2006 by Tassilo von Parseval
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This library is free software; you can redistribute it and/or modify
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it under the same terms as Perl itself, either Perl version 5.8.4 or,
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at your option, any later version of Perl 5 you may have available.
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| modules/fallback/List/MoreUtils.pm | ||
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package List::MoreUtils;
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use 5.00503;
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use strict;
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require Exporter;
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require DynaLoader;
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use vars qw($VERSION @ISA @EXPORT_OK %EXPORT_TAGS);
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@ISA = qw(Exporter DynaLoader);
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%EXPORT_TAGS = (
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all => [ qw(any all none notall true false firstidx first_index lastidx
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last_index insert_after insert_after_string apply after after_incl before
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before_incl indexes firstval first_value lastval last_value each_array
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each_arrayref pairwise natatime mesh zip uniq minmax part) ],
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);
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@EXPORT_OK = ( @{ $EXPORT_TAGS{'all'} } );
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$VERSION = '0.22';
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eval {
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local $ENV{PERL_DL_NONLAZY} = 0 if $ENV{PERL_DL_NONLAZY};
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bootstrap List::MoreUtils $VERSION;
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1;
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} if not $ENV{LIST_MOREUTILS_PP};
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eval <<'EOP' if not defined &any;
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sub any (&@) {
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my $f = shift;
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return if ! @_;
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for (@_) {
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return 1 if $f->();
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}
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return 0;
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}
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sub all (&@) {
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my $f = shift;
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return if ! @_;
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for (@_) {
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return 0 if ! $f->();
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}
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return 1;
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}
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sub none (&@) {
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my $f = shift;
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return if ! @_;
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for (@_) {
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return 0 if $f->();
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}
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return 1;
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}
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sub notall (&@) {
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my $f = shift;
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return if ! @_;
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for (@_) {
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return 1 if ! $f->();
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}
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return 0;
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}
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sub true (&@) {
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my $f = shift;
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my $count = 0;
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for (@_) {
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$count++ if $f->();
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}
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return $count;
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}
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sub false (&@) {
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my $f = shift;
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my $count = 0;
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for (@_) {
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$count++ if ! $f->();
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}
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return $count;
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}
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sub firstidx (&@) {
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my $f = shift;
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for my $i (0 .. $#_) {
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local *_ = \$_[$i];
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return $i if $f->();
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}
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return -1;
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}
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sub lastidx (&@) {
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my $f = shift;
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for my $i (reverse 0 .. $#_) {
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local *_ = \$_[$i];
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return $i if $f->();
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}
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return -1;
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}
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sub insert_after (&$\@) {
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my ($code, $val, $list) = @_;
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my $c = -1;
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local *_;
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for my $i (0 .. $#$list) {
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$_ = $list->[$i];
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$c = $i, last if $code->();
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}
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@$list = (@{$list}[0..$c], $val, @{$list}[$c+1..$#$list]) and return 1 if $c != -1;
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return 0;
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}
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sub insert_after_string ($$\@) {
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my ($string, $val, $list) = @_;
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my $c = -1;
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for my $i (0 .. $#$list) {
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local $^W = 0;
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$c = $i, last if $string eq $list->[$i];
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}
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@$list = (@{$list}[0..$c], $val, @{$list}[$c+1..$#$list]) and return 1 if $c != -1;
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return 0;
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}
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sub apply (&@) {
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my $action = shift;
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&$action for my @values = @_;
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wantarray ? @values : $values[-1];
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}
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sub after (&@)
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{
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my $test = shift;
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my $started;
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my $lag;
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grep $started ||= do { my $x=$lag; $lag=$test->(); $x}, @_;
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}
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sub after_incl (&@)
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{
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my $test = shift;
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my $started;
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grep $started ||= $test->(), @_;
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}
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sub before (&@)
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{
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my $test = shift;
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my $keepgoing=1;
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grep $keepgoing &&= !$test->(), @_;
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}
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sub before_incl (&@)
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{
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my $test = shift;
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my $keepgoing=1;
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my $lag=1;
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grep $keepgoing &&= do { my $x=$lag; $lag=!$test->(); $x}, @_;
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}
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sub indexes (&@)
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{
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my $test = shift;
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grep {local *_=\$_[$_]; $test->()} 0..$#_;
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}
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sub lastval (&@)
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{
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my $test = shift;
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my $ix;
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for ($ix=$#_; $ix>=0; $ix--)
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{
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local *_ = \$_[$ix];
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my $testval = $test->();
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$_[$ix] = $_; # simulate $_ as alias
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return $_ if $testval;
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}
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return undef;
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}
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sub firstval (&@)
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{
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my $test = shift;
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foreach (@_)
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{
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return $_ if $test->();
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}
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return undef;
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}
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sub pairwise(&\@\@)
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{
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my $op = shift;
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use vars qw/@A @B/;
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local (*A, *B) = @_; # syms for caller's input arrays
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# Localise $a, $b
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my ($caller_a, $caller_b) = do
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{
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my $pkg = caller();
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no strict 'refs';
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\*{$pkg.'::a'}, \*{$pkg.'::b'};
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};
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my $limit = $#A > $#B? $#A : $#B; # loop iteration limit
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local(*$caller_a, *$caller_b);
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map # This map expression is also the return value.
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{
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# assign to $a, $b as refs to caller's array elements
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(*$caller_a, *$caller_b) = \($A[$_], $B[$_]);
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$op->(); # perform the transformation
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} 0 .. $limit;
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}
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sub each_array (\@;\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@)
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{
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return each_arrayref(@_);
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}
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sub each_arrayref
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{
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my @arr_list = @_; # The list of references to the arrays
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my $index = 0; # Which one the caller will get next
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my $max_num = 0; # Number of elements in longest array
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# Get the length of the longest input array
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foreach (@arr_list)
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{
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unless (ref($_) eq 'ARRAY')
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{
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require Carp;
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Carp::croak "each_arrayref: argument is not an array reference\n";
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}
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$max_num = @$_ if @$_ > $max_num;
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}
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# Return the iterator as a closure wrt the above variables.
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return sub
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{
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if (@_)
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{
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my $method = shift;
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if ($method eq 'index')
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{
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# Return current (last fetched) index
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return undef if $index == 0 || $index > $max_num;
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return $index-1;
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}
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else
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{
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require Carp;
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Carp::croak "each_array: unknown argument '$method' passed to iterator.";
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}
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}
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return if $index >= $max_num; # No more elements to return
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my $i = $index++;
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return map $_->[$i], @arr_list; # Return ith elements
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}
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}
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sub natatime ($@)
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{
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my $n = shift;
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my @list = @_;
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return sub
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{
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return splice @list, 0, $n;
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}
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}
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sub mesh (\@\@;\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@) {
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my $max = -1;
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$max < $#$_ && ($max = $#$_) for @_;
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map { my $ix = $_; map $_->[$ix], @_; } 0..$max;
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}
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sub uniq (@) {
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my %h;
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map { $h{$_}++ == 0 ? $_ : () } @_;
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}
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sub minmax (@) {
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return if ! @_;
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my $min = my $max = $_[0];
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for (my $i = 1; $i < @_; $i += 2) {
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if ($_[$i-1] <= $_[$i]) {
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$min = $_[$i-1] if $min > $_[$i-1];
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$max = $_[$i] if $max < $_[$i];
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} else {
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$min = $_[$i] if $min > $_[$i];
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$max = $_[$i-1] if $max < $_[$i-1];
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}
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}
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if (@_ & 1) {
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my $i = $#_;
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if ($_[$i-1] <= $_[$i]) {
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$min = $_[$i-1] if $min > $_[$i-1];
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$max = $_[$i] if $max < $_[$i];
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} else {
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$min = $_[$i] if $min > $_[$i];
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$max = $_[$i-1] if $max < $_[$i-1];
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}
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}
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return ($min, $max);
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}
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sub part(&@) {
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my ($code, @list) = @_;
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my @parts;
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push @{ $parts[$code->($_)] }, $_ for @list;
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return @parts;
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}
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sub _XScompiled {
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return 0;
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}
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EOP
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*first_index = \&firstidx;
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*last_index = \&lastidx;
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*first_value = \&firstval;
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*last_value = \&lastval;
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*zip = \&mesh;
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1;
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__END__
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=head1 NAME
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List::MoreUtils - Provide the stuff missing in List::Util
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=head1 SYNOPSIS
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use List::MoreUtils qw(any all none notall true false firstidx first_index
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lastidx last_index insert_after insert_after_string
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apply after after_incl before before_incl indexes
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firstval first_value lastval last_value each_array
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each_arrayref pairwise natatime mesh zip uniq minmax);
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=head1 DESCRIPTION
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C<List::MoreUtils> provides some trivial but commonly needed functionality on lists
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which is not going to go into C<List::Util>.
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All of the below functions are implementable in only a couple of lines of Perl
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code. Using the functions from this module however should give slightly better
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performance as everything is implemented in C. The pure-Perl implementation of
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these functions only serves as a fallback in case the C portions of this module
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couldn't be compiled on this machine.
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=over 4
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=item any BLOCK LIST
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Returns a true value if any item in LIST meets the criterion given through
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BLOCK. Sets C<$_> for each item in LIST in turn:
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print "At least one value undefined"
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if any { !defined($_) } @list;
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Returns false otherwise, or C<undef> if LIST is empty.
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=item all BLOCK LIST
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Returns a true value if all items in LIST meet the criterion given through
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BLOCK. Sets C<$_> for each item in LIST in turn:
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print "All items defined"
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if all { defined($_) } @list;
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Returns false otherwise, or C<undef> if LIST is empty.
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=item none BLOCK LIST
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Logically the negation of C<any>. Returns a true value if no item in LIST meets the
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criterion given through BLOCK. Sets C<$_> for each item in LIST in turn:
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print "No value defined"
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if none { defined($_) } @list;
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Returns false otherwise, or C<undef> if LIST is empty.
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=item notall BLOCK LIST
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Logically the negation of C<all>. Returns a true value if not all items in LIST meet
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the criterion given through BLOCK. Sets C<$_> for each item in LIST in turn:
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print "Not all values defined"
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if notall { defined($_) } @list;
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Returns false otherwise, or C<undef> if LIST is empty.
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=item true BLOCK LIST
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Counts the number of elements in LIST for which the criterion in BLOCK is true. Sets C<$_> for
|
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each item in LIST in turn:
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printf "%i item(s) are defined", true { defined($_) } @list;
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=item false BLOCK LIST
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Counts the number of elements in LIST for which the criterion in BLOCK is false. Sets C<$_> for
|
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each item in LIST in turn:
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printf "%i item(s) are not defined", false { defined($_) } @list;
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=item firstidx BLOCK LIST
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=item first_index BLOCK LIST
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Returns the index of the first element in LIST for which the criterion in BLOCK is true. Sets C<$_>
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for each item in LIST in turn:
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my @list = (1, 4, 3, 2, 4, 6);
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printf "item with index %i in list is 4", firstidx { $_ == 4 } @list;
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__END__
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item with index 1 in list is 4
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Returns C<-1> if no such item could be found.
|
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C<first_index> is an alias for C<firstidx>.
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=item lastidx BLOCK LIST
|
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=item last_index BLOCK LIST
|
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Returns the index of the last element in LIST for which the criterion in BLOCK is true. Sets C<$_>
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for each item in LIST in turn:
|
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my @list = (1, 4, 3, 2, 4, 6);
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printf "item with index %i in list is 4", lastidx { $_ == 4 } @list;
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|
__END__
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item with index 4 in list is 4
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Returns C<-1> if no such item could be found.
|
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|
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C<last_index> is an alias for C<lastidx>.
|
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|
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=item insert_after BLOCK VALUE LIST
|
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Inserts VALUE after the first item in LIST for which the criterion in BLOCK is true. Sets C<$_> for
|
||
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each item in LIST in turn.
|
||
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|
||
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my @list = qw/This is a list/;
|
||
|
insert_after { $_ eq "a" } "longer" => @list;
|
||
|
print "@list";
|
||
|
__END__
|
||
|
This is a longer list
|
||
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|
||
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=item insert_after_string STRING VALUE LIST
|
||
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|
||
|
Inserts VALUE after the first item in LIST which is equal to STRING.
|
||
|
|
||
|
my @list = qw/This is a list/;
|
||
|
insert_after_string "a", "longer" => @list;
|
||
|
print "@list";
|
||
|
__END__
|
||
|
This is a longer list
|
||
|
|
||
|
=item apply BLOCK LIST
|
||
|
|
||
|
Applies BLOCK to each item in LIST and returns a list of the values after BLOCK
|
||
|
has been applied. In scalar context, the last element is returned. This
|
||
|
function is similar to C<map> but will not modify the elements of the input
|
||
|
list:
|
||
|
|
||
|
my @list = (1 .. 4);
|
||
|
my @mult = apply { $_ *= 2 } @list;
|
||
|
print "\@list = @list\n";
|
||
|
print "\@mult = @mult\n";
|
||
|
__END__
|
||
|
@list = 1 2 3 4
|
||
|
@mult = 2 4 6 8
|
||
|
|
||
|
Think of it as syntactic sugar for
|
||
|
|
||
|
for (my @mult = @list) { $_ *= 2 }
|
||
|
|
||
|
=item after BLOCK LIST
|
||
|
|
||
|
Returns a list of the values of LIST after (and not including) the point
|
||
|
where BLOCK returns a true value. Sets C<$_> for each element in LIST in turn.
|
||
|
|
||
|
@x = after { $_ % 5 == 0 } (1..9); # returns 6, 7, 8, 9
|
||
|
|
||
|
=item after_incl BLOCK LIST
|
||
|
|
||
|
Same as C<after> but also inclues the element for which BLOCK is true.
|
||
|
|
||
|
=item before BLOCK LIST
|
||
|
|
||
|
Returns a list of values of LIST upto (and not including) the point where BLOCK
|
||
|
returns a true value. Sets C<$_> for each element in LIST in turn.
|
||
|
|
||
|
=item before_incl BLOCK LIST
|
||
|
|
||
|
Same as C<before> but also includes the element for which BLOCK is true.
|
||
|
|
||
|
=item indexes BLOCK LIST
|
||
|
|
||
|
Evaluates BLOCK for each element in LIST (assigned to C<$_>) and returns a list
|
||
|
of the indices of those elements for which BLOCK returned a true value. This is
|
||
|
just like C<grep> only that it returns indices instead of values:
|
||
|
|
||
|
@x = indexes { $_ % 2 == 0 } (1..10); # returns 1, 3, 5, 7, 9
|
||
|
|
||
|
=item firstval BLOCK LIST
|
||
|
|
||
|
=item first_value BLOCK LIST
|
||
|
|
||
|
Returns the first element in LIST for which BLOCK evaluates to true. Each
|
||
|
element of LIST is set to C<$_> in turn. Returns C<undef> if no such element
|
||
|
has been found.
|
||
|
|
||
|
C<first_val> is an alias for C<firstval>.
|
||
|
|
||
|
=item lastval BLOCK LIST
|
||
|
|
||
|
=item last_value BLOCK LIST
|
||
|
|
||
|
Returns the last value in LIST for which BLOCK evaluates to true. Each element
|
||
|
of LIST is set to C<$_> in turn. Returns C<undef> if no such element has been
|
||
|
found.
|
||
|
|
||
|
C<last_val> is an alias for C<lastval>.
|
||
|
|
||
|
=item pairwise BLOCK ARRAY1 ARRAY2
|
||
|
|
||
|
Evaluates BLOCK for each pair of elements in ARRAY1 and ARRAY2 and returns a
|
||
|
new list consisting of BLOCK's return values. The two elements are set to C<$a>
|
||
|
and C<$b>. Note that those two are aliases to the original value so changing
|
||
|
them will modify the input arrays.
|
||
|
|
||
|
@a = (1 .. 5);
|
||
|
@b = (11 .. 15);
|
||
|
@x = pairwise { $a + $b } @a, @b; # returns 12, 14, 16, 18, 20
|
||
|
|
||
|
# mesh with pairwise
|
||
|
@a = qw/a b c/;
|
||
|
@b = qw/1 2 3/;
|
||
|
@x = pairwise { ($a, $b) } @a, @b; # returns a, 1, b, 2, c, 3
|
||
|
|
||
|
=item each_array ARRAY1 ARRAY2 ...
|
||
|
|
||
|
Creates an array iterator to return the elements of the list of arrays ARRAY1,
|
||
|
ARRAY2 throughout ARRAYn in turn. That is, the first time it is called, it
|
||
|
returns the first element of each array. The next time, it returns the second
|
||
|
elements. And so on, until all elements are exhausted.
|
||
|
|
||
|
This is useful for looping over more than one array at once:
|
||
|
|
||
|
my $ea = each_array(@a, @b, @c);
|
||
|
while ( my ($a, $b, $c) = $ea->() ) { .... }
|
||
|
|
||
|
The iterator returns the empty list when it reached the end of all arrays.
|
||
|
|
||
|
If the iterator is passed an argument of 'C<index>', then it retuns
|
||
|
the index of the last fetched set of values, as a scalar.
|
||
|
|
||
|
=item each_arrayref LIST
|
||
|
|
||
|
Like each_array, but the arguments are references to arrays, not the
|
||
|
plain arrays.
|
||
|
|
||
|
=item natatime BLOCK LIST
|
||
|
|
||
|
Creates an array iterator, for looping over an array in chunks of
|
||
|
C<$n> items at a time. (n at a time, get it?). An example is
|
||
|
probably a better explanation than I could give in words.
|
||
|
|
||
|
Example:
|
||
|
|
||
|
my @x = ('a' .. 'g');
|
||
|
my $it = natatime 3, @x;
|
||
|
while (my @vals = $it->())
|
||
|
{
|
||
|
print "@vals\n";
|
||
|
}
|
||
|
|
||
|
This prints
|
||
|
|
||
|
a b c
|
||
|
d e f
|
||
|
g
|
||
|
|
||
|
=item mesh ARRAY1 ARRAY2 [ ARRAY3 ... ]
|
||
|
|
||
|
=item zip ARRAY1 ARRAY2 [ ARRAY3 ... ]
|
||
|
|
||
|
Returns a list consisting of the first elements of each array, then
|
||
|
the second, then the third, etc, until all arrays are exhausted.
|
||
|
|
||
|
Examples:
|
||
|
|
||
|
@x = qw/a b c d/;
|
||
|
@y = qw/1 2 3 4/;
|
||
|
@z = mesh @x, @y; # returns a, 1, b, 2, c, 3, d, 4
|
||
|
|
||
|
@a = ('x');
|
||
|
@b = ('1', '2');
|
||
|
@c = qw/zip zap zot/;
|
||
|
@d = mesh @a, @b, @c; # x, 1, zip, undef, 2, zap, undef, undef, zot
|
||
|
|
||
|
C<zip> is an alias for C<mesh>.
|
||
|
|
||
|
=item uniq LIST
|
||
|
|
||
|
Returns a new list by stripping duplicate values in LIST. The order of
|
||
|
elements in the returned list is the same as in LIST. In scalar context,
|
||
|
returns the number of unique elements in LIST.
|
||
|
|
||
|
my @x = uniq 1, 1, 2, 2, 3, 5, 3, 4; # returns 1 2 3 5 4
|
||
|
my $x = uniq 1, 1, 2, 2, 3, 5, 3, 4; # returns 5
|
||
|
|
||
|
=item minmax LIST
|
||
|
|
||
|
Calculates the minimum and maximum of LIST and returns a two element list with
|
||
|
the first element being the minimum and the second the maximum. Returns the empty
|
||
|
list if LIST was empty.
|
||
|
|
||
|
The minmax algorithm differs from a naive iteration over the list where each element
|
||
|
is compared to two values being the so far calculated min and max value in that it
|
||
|
only requires 3n/2 - 2 comparisons. Thus it is the most efficient possible algorithm.
|
||
|
|
||
|
However, the Perl implementation of it has some overhead simply due to the fact
|
||
|
that there are more lines of Perl code involved. Therefore, LIST needs to be
|
||
|
fairly big in order for minmax to win over a naive implementation. This
|
||
|
limitation does not apply to the XS version.
|
||
|
|
||
|
=item part BLOCK LIST
|
||
|
|
||
|
Partitions LIST based on the return value of BLOCK which denotes into which partition
|
||
|
the current value is put.
|
||
|
|
||
|
Returns a list of the partitions thusly created. Each partition created is a
|
||
|
reference to an array.
|
||
|
|
||
|
my $i = 0;
|
||
|
my @part = part { $i++ % 2 } 1 .. 8; # returns [1, 3, 5, 7], [2, 4, 6, 8]
|
||
|
|
||
|
You can have a sparse list of partitions as well where non-set partitions will
|
||
|
be undef:
|
||
|
|
||
|
my @part = part { 2 } 1 .. 10; # returns undef, undef, [ 1 .. 10 ]
|
||
|
|
||
|
Be careful with negative values, though:
|
||
|
|
||
|
my @part = part { -1 } 1 .. 10;
|
||
|
__END__
|
||
|
Modification of non-creatable array value attempted, subscript -1 ...
|
||
|
|
||
|
Negative values are only ok when they refer to a partition previously created:
|
||
|
|
||
|
my @idx = (0, 1, -1);
|
||
|
my $i = 0;
|
||
|
my @part = part { $idx[$++ % 3] } 1 .. 8; # [1, 4, 7], [2, 3, 5, 6, 8]
|
||
|
|
||
|
=back
|
||
|
|
||
|
=head1 EXPORTS
|
||
|
|
||
|
Nothing by default. To import all of this module's symbols, do the conventional
|
||
|
|
||
|
use List::MoreUtils qw/:all/;
|
||
|
|
||
|
It may make more sense though to only import the stuff your program actually needs:
|
||
|
|
||
|
use List::MoreUtils qw/any firstidx/;
|
||
|
|
||
|
=head1 ENVIRONMENT
|
||
|
|
||
|
When C<LIST_MOREUTILS_PP> is set, the module will always use the pure-Perl
|
||
|
implementation and not the XS one. This environment variable is really just
|
||
|
there for the test-suite to force testing the Perl implementation, and possibly
|
||
|
for reporting of bugs. I don't see any reason to use it in a production
|
||
|
environment.
|
||
|
|
||
|
=head1 VERSION
|
||
|
|
||
|
This is version 0.22.
|
||
|
|
||
|
=head1 BUGS
|
||
|
|
||
|
There is a problem with a bug in 5.6.x perls. It is a syntax error to write
|
||
|
things like:
|
||
|
|
||
|
my @x = apply { s/foo/bar/ } qw/foo bar baz/;
|
||
|
|
||
|
It has to be written as either
|
||
|
|
||
|
my @x = apply { s/foo/bar/ } 'foo', 'bar', 'baz';
|
||
|
|
||
|
or
|
||
|
|
||
|
my @x = apply { s/foo/bar/ } my @dummy = qw/foo bar baz/;
|
||
|
|
||
|
Perl5.5.x and perl5.8.x don't suffer from this limitation.
|
||
|
|
||
|
If you have a functionality that you could imagine being in this module, please
|
||
|
drop me a line. This module's policy will be less strict than C<List::Util>'s when
|
||
|
it comes to additions as it isn't a core module.
|
||
|
|
||
|
When you report bugs, it would be nice if you could additionally give me the
|
||
|
output of your program with the environment variable C<LIST_MOREUTILS_PP> set
|
||
|
to a true value. That way I know where to look for the problem (in XS,
|
||
|
pure-Perl or possibly both).
|
||
|
|
||
|
=head1 THANKS
|
||
|
|
||
|
Credits go to a number of people: Steve Purkis for giving me namespace advice
|
||
|
and James Keenan and Terrence Branno for their effort of keeping the CPAN
|
||
|
tidier by making List::Utils obsolete.
|
||
|
|
||
|
Brian McCauley suggested the inclusion of apply() and provided the pure-Perl
|
||
|
implementation for it.
|
||
|
|
||
|
Eric J. Roode asked me to add all functions from his module C<List::MoreUtil>
|
||
|
into this one. With minor modifications, the pure-Perl implementations of those
|
||
|
are by him.
|
||
|
|
||
|
The bunch of people who almost immediately pointed out the many problems with
|
||
|
the glitchy 0.07 release (Slaven Rezic, Ron Savage, CPAN testers).
|
||
|
|
||
|
A particularly nasty memory leak was spotted by Thomas A. Lowery.
|
||
|
|
||
|
Lars Thegler made me aware of problems with older Perl versions.
|
||
|
|
||
|
Anno Siegel de-orphaned each_arrayref().
|
||
|
|
||
|
David Filmer made me aware of a problem in each_arrayref that could ultimately
|
||
|
lead to a segfault.
|
||
|
|
||
|
Ricardo Signes suggested the inclusion of part() and provided the
|
||
|
Perl-implementation.
|
||
|
|
||
|
Robin Huston kindly fixed a bug in perl's MULTICALL API to make the
|
||
|
XS-implementation of part() work.
|
||
|
|
||
|
=head1 TODO
|
||
|
|
||
|
A pile of requests from other people is still pending further processing in my
|
||
|
mailbox. This includes:
|
||
|
|
||
|
=over 4
|
||
|
|
||
|
=item * uniq_by(&@)
|
||
|
|
||
|
Use code-reference to extract a key based on which the uniqueness is
|
||
|
determined. Suggested by Aaron Crane.
|
||
|
|
||
|
=item * delete_index
|
||
|
|
||
|
=item * random_item
|
||
|
|
||
|
=item * random_item_delete_index
|
||
|
|
||
|
=item * list_diff_hash
|
||
|
|
||
|
=item * list_diff_inboth
|
||
|
|
||
|
=item * list_diff_infirst
|
||
|
|
||
|
=item * list_diff_insecond
|
||
|
|
||
|
These were all suggested by Dan Muey.
|
||
|
|
||
|
=item * listify
|
||
|
|
||
|
Always return a flat list when either a simple scalar value was passed or an array-reference.
|
||
|
Suggested by Mark Summersault.
|
||
|
|
||
|
=back
|
||
|
|
||
|
=head1 SEE ALSO
|
||
|
|
||
|
L<List::Util>
|
||
|
|
||
|
=head1 AUTHOR
|
||
|
|
||
|
Tassilo von Parseval, E<lt>tassilo.von.parseval@rwth-aachen.deE<gt>
|
||
|
|
||
|
=head1 COPYRIGHT AND LICENSE
|
||
|
|
||
|
Copyright (C) 2004-2006 by Tassilo von Parseval
|
||
|
|
||
|
This library is free software; you can redistribute it and/or modify
|
||
|
it under the same terms as Perl itself, either Perl version 5.8.4 or,
|
||
|
at your option, any later version of Perl 5 you may have available.
|
||
|
|
||
|
=cut
|
||
Auch abrufbar als: Unified diff
Das Perl-Modul "List::MoreUtils" als Fallback hinzugefügt.
Damit ist es möglich, List::MoreUtils einzusetzen, ohne sich Gedanken
darüber machen zu müssen, ob es installiert ist.