SYNOPSIS

     use Array::Set qw(set_diff set_symdiff set_union set_intersect);
    
     set_diff([1,2,3,4], [2,3,4,5]);            # => [1]
     set_diff([1,2,3,4], [2,3,4,5], [3,4,5,6]); # => [1]
     set_diff({ignore_case=>1}, ["a","b"], ["B","c"]);   # => ["a"]
    
     set_symdiff([1,2,3,4], [2,3,4,5]);            # => [1,5]
     set_symdiff([1,2,3,4], [2,3,4,5], [3,4,5,6]); # => [1,6]
    
     set_union([1,3,2,4], [2,3,4,5]);            # => [1,3,2,4,5]
     set_union([1,3,2,4], [2,3,4,5], [3,4,5,6]); # => [1,3,2,4,5,6]
    
     set_intersect([1,2,3,4], [2,3,4,5]);            # => [2,3,4]
     set_intersect([1,2,3,4], [2,3,4,5], [3,4,5,6]); # => [3,4]

DESCRIPTION

    This module provides routines for performing set operations on arrays.
    Set is represented as a regular Perl array. All comparison is currently
    done with eq (string comparison) so currently no support for
    references/objects/undefs. You have to make sure that the arrays do not
    contain duplicates/undefs.

    Characteristics and differences with other similar modules:

      * simple functional (non-OO) interface

      * functions accept more than two arguments

      * option to do case-insensitive comparison

      * option to ignore blanks

      * preserves ordering

FUNCTIONS

    All functions are not exported by default, but exportable.

 set_diff([ \%opts ], \@set1, ...) => array

    Perform difference (find elements in the first set not in the other
    sets). Accept optional hashref as the first argument for options. Known
    options:

      * ignore_case => bool (default: 0)

      If set to 1, will perform case-insensitive comparison.

      * ignore_blanks => bool (default: 0)

      If set to 1, will ignore blanks (" foo" == "foo" == "f o o").

 set_symdiff([ \%opts ], \@set1, ...) => array

    Perform symmetric difference (find elements in the first set not in the
    other set, as well as elements in the other set not in the first).
    Accept optional hashref as the first argument for options. See set_diff
    for known options.

 set_union([ \%opts ], \@set1, ...) => array

    Perform union (find elements in the first or in the other, duplicates
    removed). Accept optional hashref as the first argument for options.
    See set_diff for known options.

 set_intersect([ \%opts ], \@set1, ...) => array

    Perform intersection (find elements common in all the sets). Accept
    optional hashref as the first argument for options. See set_diff for
    known options.

SEE ALSO

    See some benchmarks in Bencher::Scenarios::ArraySet.

    App::setop to perform set operations on lines of files on the
    command-line.

    Array::Utils, Set::Scalar, List::MoreUtils (uniq for union, singleton
    for symmetric diff), Set::Array, Array::AsObject, Set::Object,
    Set::Tiny.