NAME
    Set::Tiny - Simple sets of strings

SYNOPSIS
        use Set::Tiny;

        my $s1 = Set::Tiny->new(qw( a b c ));
        my $s2 = Set::Tiny->new(qw( b c d ));

        my $u  = $s1->union($s2);
        my $i  = $s1->intersection($s2);
        my $s  = $s1->symmetric_difference($s2);

        print $u->as_string; # (a b c d)
        print $i->as_string; # (b c)
        print $s->as_string; # (a d)

        print "i is a subset of s1"   if $i->is_subset($s1);
        print "u is a superset of s1" if $u->is_superset($s1);

        # or using the shorter initializer:

        use Set::Tiny qw( set );

        my $s1 = set(qw( a b c ));
        my $s2 = set([1, 2, 3]);

DESCRIPTION
    Set::Tiny is a thin wrapper around regular Perl hashes to perform often
    needed set operations, such as testing two sets of strings for equality,
    or checking whether one is contained within the other.

    For a more complete implementation of mathematical set theory, see
    Set::Scalar. For sets of arbitrary objects, see Set::Object.

  Why Set::Tiny?
    Convenience
        "Set::Tiny" aims to provide a convenient interface to commonly used
        set operations, which you would usually implement using regular
        hashes and a couple of "for" loops (in fact, that's exactly what
        "Set::Tiny" does).

    Speed
        The price in performance you pay for this convenience when using a
        full-featured set implementation like Set::Scalar is way too high if
        you don't actually need the advanced functionality it offers. Run
        examples/benchmark.pl for a (non-representative) comparison between
        different "Set::" modules.

    Ease of use
        Set::Object offers better performance than Set::Scalar, but needs a
        C compiler to install. "Set::Tiny" has no dependencies and contains
        no C code.

EXPORTABLE FUNCTIONS
  set( [*list or arrayref*] )
    If you request it, Set::Tiny can export a function set(), which lets you
    create a Set::Tiny instance in a more compact form.

    Unlike the constructor, this function also accepts the set elements as
    an array reference.

    If you pass an existing Set::Tiny to the initializer, it creates a clone
    of the set and returns that.

METHODS
    Note that all methods that expect a *list* of set elements stringify
    their arguments before inserting them into the set.

  new( [*list*] )
    Class method. Returns a new Set::Tiny object, initialized with the
    strings in *list*, or the empty set if *list* is empty.

  clone
  copy
    Returns a new set with the same elements as this one.

  insert( [*list*] )
    Inserts the elements in *list* into the set.

  delete( [*list*] )
  remove( [*list*] )
    Removes the elements in *list* from the set. Elements that are not
    members of the set are ignored.

  invert( [*list*] )
    For each element in *list*, if it is already a member of the set,
    deletes it from the set, else insert it into the set.

  clear
    Removes all elements from the set.

  as_string
    Returns a string representation of the set.

  elements
  members
    Returns the (unordered) list of elements.

  size
    Returns the number of elements.

  has( [*list*] )
  contains( [*list*] )
    Returns true if all of the elements in *list* are members of the set. If
    *list* is empty, returns true.

  element( [*string*] )
  member( [*string*] )
    Returns the string if it is contained in the set.

  is_null
  is_empty
    Returns true if the set is the empty set.

  union( *set* )
    Returns a new set containing both the elements of this set and *set*.

  intersection( *set* )
    Returns a new set containing the elements that are present in both this
    set and *set*.

  intersection2( *set* )
    Like intersection(), but orders the sets by size before comparing their
    elements. This results in a small overhead for small, evenly sized sets,
    but a large speedup when comparing bigger (~ 100 elements) and very
    unevenly sized sets.

  difference( *set* )
    Returns a new set containing the elements of this set with the elements
    of *set* removed.

  unique( *set* )
  symmetric_difference( *set* )
    Returns a new set containing the elements that are present in either
    this set or *set*, but not in both.

  is_equal( *set* )
    Returns true if this set contains the same elements as *set*.

  is_disjoint( *set* )
    Returns true if this set has no elements in common with *set*. Note that
    the empty set is disjoint to any other set.

  is_properly_intersecting( *set* )
    Returns true if this set has elements in common with *set*, but both
    also contain elements that they have not in common with each other.

  is_proper_subset( *set* )
    Returns true if this set is a proper subset of *set*.

  is_proper_superset( *set* )
    Returns true if this set is a proper superset of *set*.

  is_subset( *set* )
    Returns true if this set is a subset of *set*.

  is_superset( *set* )
    Returns true if this set is a superset of *set*.

AUTHOR
    Stanis Trendelenburg, "<trendels at cpan.org>"

CREDITS
    Thanks to Adam Kennedy for advice on how to make this module "Tiny".

SEE ALSO
    *   Set::Scalar

BUGS
    Please report any bugs or feature requests on the bugtracker website
    <https://github.com/haarg/Set-Tiny/issues>

    When submitting a bug or request, please include a test-file or a patch
    to an existing test-file that illustrates the bug or desired feature.

CONTRIBUTORS
    *   Alberto Manuel Brandão Simões <ambs@cpan.org>

    *   Alceu Rodrigues de Freitas Junior <glasswalk3r@yahoo.com.br>

    *   brian greenfield <briang@cpan.org>

    *   Graham Knop <haarg@haarg.org>

    *   Ricky Morse <remorse@mgh.harvard.edu>

    *   Stanis Trendelenburg <stanis.trendelenburg@gmail.com>

AUTHOR
    Stanis Trendelenburg <trendels@cpan.org>

COPYRIGHT AND LICENSE
    This software is copyright (c) 2024 by Stanis Trendelenburg.

    This is free software; you can redistribute it and/or modify it under
    the same terms as the Perl 5 programming language system itself.