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README
NAME
    List::AllUtils - Combines List::Util and List::MoreUtils in one
    bite-sized package

SYNOPSIS
        use List::AllUtils qw( first any );

        # _Everything_ from List::Util and List::MoreUtils
        use List::AllUtils qw( :all );

        # or don't import anything
        return List::AllUtils::first { $_ > 5 } @numbers;

DESCRIPTION
    Are you sick of trying to remember whether a particular helper is
    defined in `List::Util' or `List::MoreUtils'? I sure am. Now you don't
    have to remember. This module will export all of the functions that
    either of those two modules defines.

FUNCTIONS
    (Shamelessly copied from List::Util and List::MoreUtils ...)

  first BLOCK LIST
    Similar to `grep' in that it evaluates BLOCK setting `$_' to each
    element of LIST in turn. `first' returns the first element where the
    result from BLOCK is a true value. If BLOCK never returns true or LIST
    was empty then `undef' is returned.

        $foo = first { defined($_) } @list    # first defined value in @list
        $foo = first { $_ > $value } @list    # first value in @list which
                                              # is greater than $value

    This function could be implemented using `reduce' like this

        $foo = reduce { wanted($a) ? $a : wanted($b) ? $b : undef } undef, @list

    for example wanted() could be defined() which would return the first
    defined value in @list

  max LIST
    Returns the entry in the list with the highest numerical value. If the
    list is empty then `undef' is returned.

        $foo = max 1..10                # 10
        $foo = max 3,9,12               # 12
        $foo = max @bar, @baz           # whatever

    This function could be implemented using `reduce' like this

        $foo = reduce { $a > $b ? $a : $b } 1..10

  maxstr LIST
    Similar to `max', but treats all the entries in the list as strings and
    returns the highest string as defined by the `gt' operator. If the list
    is empty then `undef' is returned.

        $foo = maxstr 'A'..'Z'          # 'Z'
        $foo = maxstr "hello","world"   # "world"
        $foo = maxstr @bar, @baz        # whatever

    This function could be implemented using `reduce' like this

        $foo = reduce { $a gt $b ? $a : $b } 'A'..'Z'

  min LIST
    Similar to `max' but returns the entry in the list with the lowest
    numerical value. If the list is empty then `undef' is returned.

        $foo = min 1..10                # 1
        $foo = min 3,9,12               # 3
        $foo = min @bar, @baz           # whatever

    This function could be implemented using `reduce' like this

        $foo = reduce { $a < $b ? $a : $b } 1..10

  minstr LIST
    Similar to `min', but treats all the entries in the list as strings and
    returns the lowest string as defined by the `lt' operator. If the list
    is empty then `undef' is returned.

        $foo = minstr 'A'..'Z'          # 'A'
        $foo = minstr "hello","world"   # "hello"
        $foo = minstr @bar, @baz        # whatever

    This function could be implemented using `reduce' like this

        $foo = reduce { $a lt $b ? $a : $b } 'A'..'Z'

  reduce BLOCK LIST
    Reduces LIST by calling BLOCK, in a scalar context, multiple times,
    setting `$a' and `$b' each time. The first call will be with `$a' and
    `$b' set to the first two elements of the list, subsequent calls will be
    done by setting `$a' to the result of the previous call and `$b' to the
    next element in the list.

    Returns the result of the last call to BLOCK. If LIST is empty then
    `undef' is returned. If LIST only contains one element then that element
    is returned and BLOCK is not executed.

        $foo = reduce { $a < $b ? $a : $b } 1..10       # min
        $foo = reduce { $a lt $b ? $a : $b } 'aa'..'zz' # minstr
        $foo = reduce { $a + $b } 1 .. 10               # sum
        $foo = reduce { $a . $b } @bar                  # concat

  shuffle LIST
    Returns the elements of LIST in a random order

        @cards = shuffle 0..51      # 0..51 in a random order

  sum LIST
    Returns the sum of all the elements in LIST. If LIST is empty then
    `undef' is returned.

        $foo = sum 1..10                # 55
        $foo = sum 3,9,12               # 24
        $foo = sum @bar, @baz           # whatever

    This function could be implemented using `reduce' like this

        $foo = reduce { $a + $b } 1..10

  any BLOCK LIST
    Returns a true value if any item in LIST meets the criterion given
    through BLOCK. Sets `$_' for each item in LIST in turn:

        print "At least one value undefined"
            if any { !defined($_) } @list;

    Returns false otherwise, or `undef' if LIST is empty.

  all BLOCK LIST
    Returns a true value if all items in LIST meet the criterion given
    through BLOCK. Sets `$_' for each item in LIST in turn:

        print "All items defined"
            if all { defined($_) } @list;

    Returns false otherwise, or `undef' if LIST is empty.

  none BLOCK LIST
    Logically the negation of `any'. Returns a true value if no item in LIST
    meets the criterion given through BLOCK. Sets `$_' for each item in LIST
    in turn:

        print "No value defined"
            if none { defined($_) } @list;

    Returns false otherwise, or `undef' if LIST is empty.

  notall BLOCK LIST
    Logically the negation of `all'. Returns a true value if not all items
    in LIST meet the criterion given through BLOCK. Sets `$_' for each item
    in LIST in turn:

        print "Not all values defined"
            if notall { defined($_) } @list;

    Returns false otherwise, or `undef' if LIST is empty.

  true BLOCK LIST
    Counts the number of elements in LIST for which the criterion in BLOCK
    is true. Sets `$_' for each item in LIST in turn:

        printf "%i item(s) are defined", true { defined($_) } @list;

  false BLOCK LIST
    Counts the number of elements in LIST for which the criterion in BLOCK
    is false. Sets `$_' for each item in LIST in turn:

        printf "%i item(s) are not defined", false { defined($_) } @list;

  firstidx BLOCK LIST
  first_index BLOCK LIST
    Returns the index of the first element in LIST for which the criterion
    in BLOCK is true. Sets `$_' for each item in LIST in turn:

        my @list = (1, 4, 3, 2, 4, 6);
        printf "item with index %i in list is 4", firstidx { $_ == 4 } @list;
        __END__
        item with index 1 in list is 4

    Returns `-1' if no such item could be found.

    `first_index' is an alias for `firstidx'.

  lastidx BLOCK LIST
  last_index BLOCK LIST
    Returns the index of the last element in LIST for which the criterion in
    BLOCK is true. Sets `$_' for each item in LIST in turn:

        my @list = (1, 4, 3, 2, 4, 6);
        printf "item with index %i in list is 4", lastidx { $_ == 4 } @list;
        __END__
        item with index 4 in list is 4

    Returns `-1' if no such item could be found.

    `last_index' is an alias for `lastidx'.

  insert_after BLOCK VALUE LIST
    Inserts VALUE after the first item in LIST for which the criterion in
    BLOCK is true. Sets `$_' for each item in LIST in turn.

        my @list = qw/This is a list/;
        insert_after { $_ eq "a" } "longer" => @list;
        print "@list";
        __END__
        This is a longer list

  insert_after_string STRING VALUE LIST
    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

  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 `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 }

  after BLOCK LIST
    Returns a list of the values of LIST after (and not including) the point
    where BLOCK returns a true value. Sets `$_' for each element in LIST in
    turn.

        @x = after { $_ % 5 == 0 } (1..9);    # returns 6, 7, 8, 9

  after_incl BLOCK LIST
    Same as `after' but also inclues the element for which BLOCK is true.

  before BLOCK LIST
    Returns a list of values of LIST upto (and not including) the point
    where BLOCK returns a true value. Sets `$_' for each element in LIST in
    turn.

  before_incl BLOCK LIST
    Same as `before' but also includes the element for which BLOCK is true.

  indexes BLOCK LIST
    Evaluates BLOCK for each element in LIST (assigned to `$_') and returns
    a list of the indices of those elements for which BLOCK returned a true
    value. This is just like `grep' only that it returns indices instead of
    values:

        @x = indexes { $_ % 2 == 0 } (1..10);   # returns 1, 3, 5, 7, 9

  firstval BLOCK LIST
  first_value BLOCK LIST
    Returns the first element in LIST for which BLOCK evaluates to true.
    Each element of LIST is set to `$_' in turn. Returns `undef' if no such
    element has been found.

    `first_val' is an alias for `firstval'.

  lastval BLOCK LIST
  last_value BLOCK LIST
    Returns the last value in LIST for which BLOCK evaluates to true. Each
    element of LIST is set to `$_' in turn. Returns `undef' if no such
    element has been found.

    `last_val' is an alias for `lastval'.

  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 `$a' and `$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

  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 '`index'', then it retuns the
    index of the last fetched set of values, as a scalar.

  each_arrayref LIST
    Like each_array, but the arguments are references to arrays, not the
    plain arrays.

  natatime BLOCK LIST
    Creates an array iterator, for looping over an array in chunks of `$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

  mesh ARRAY1 ARRAY2 [ ARRAY3 ... ]
  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

    `zip' is an alias for `mesh'.

  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

  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.

  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]

EXPORTS
    This module exports nothing by default. You can import functions by
    name, or get everything with the `:all' tag.

SEE ALSO
    `List::Util' and `List::MoreUtils', obviously.

    Also see `Util::Any', which unifies many more util modules, and also
    lets you rename functions as part of the import.

AUTHOR
    Dave Rolsky, `<autarch@urth.org>'

    But really, this module does very little, and all the docs come from
    List::Util by Graham Barr and List::MoreUtils by Tassilo von Parseval.

BUGS
    Please report any bugs or feature requests to
    `bug-list-allutils@rt.cpan.org', or through the web interface at
    http://rt.cpan.org. I will be notified, and then you'll automatically be
    notified of progress on your bug as I make changes.

COPYRIGHT & LICENSE
    Copyright 2009 Dave Rolsky, All Rights Reserved.

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

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