struct::set(n)                Tcl Data Structures               struct::set(n)



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NAME
       struct::set - Procedures for manipulating sets

SYNOPSIS
       package require Tcl  8.0

       package require struct::set  ?2.2.3?

       ::struct::set empty set

       ::struct::set size set

       ::struct::set contains set item

       ::struct::set union ?set1...?

       ::struct::set intersect ?set1...?

       ::struct::set difference set1 set2

       ::struct::set symdiff set1 set2

       ::struct::set intersect3 set1 set2

       ::struct::set equal set1 set2

       ::struct::set include svar item

       ::struct::set exclude svar item

       ::struct::set add svar set

       ::struct::set subtract svar set

       ::struct::set subsetof A B

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DESCRIPTION
       The ::struct::set namespace contains several useful commands for
       processing finite sets.

       It exports only a single command, struct::set. All functionality
       provided here can be reached through a subcommand of this command.

       Note: As of version 2.2 of this package a critcl based C implementation
       is available. This implementation however requires Tcl 8.4 to run.

COMMANDS
       ::struct::set empty set
              Returns a boolean value indicating if the set is empty (true),
              or not (false).

       ::struct::set size set
              Returns an integer number greater than or equal to zero. This is
              the number of elements in the set. In other words, its
              cardinality.

       ::struct::set contains set item
              Returns a boolean value indicating if the set contains the
              element item (true), or not (false).

       ::struct::set union ?set1...?
              Computes the set containing the union of set1, set2, etc., i.e.
              "set1 + set2 + ...", and returns this set as the result of the
              command.

       ::struct::set intersect ?set1...?
              Computes the set containing the intersection of set1, set2,
              etc., i.e. "set1 * set2 * ...", and returns this set as the
              result of the command.

       ::struct::set difference set1 set2
              Computes the set containing the difference of set1 and set2,
              i.e. ("set1 - set2") and returns this set as the result of the
              command.

       ::struct::set symdiff set1 set2
              Computes the set containing the symmetric difference of set1 and
              set2, i.e. ("(set1 - set2) + (set2 - set1)") and returns this
              set as the result of the command.

       ::struct::set intersect3 set1 set2
              This command is a combination of the methods intersect and
              difference.  It returns a three-element list containing
              "set1*set2", "set1-set2", and "set2-set1", in this order. In
              other words, the intersection of the two parameter sets, and
              their differences.

       ::struct::set equal set1 set2
              Returns a boolean value indicating if the two sets are equal
              (true) or not (false).

       ::struct::set include svar item
              The element item is added to the set specified by the variable
              name in svar. The return value of the command is empty. This is
              the equivalent of lappend for sets. If the variable named by
              svar does not exist it will be created.

       ::struct::set exclude svar item
              The element item is removed from the set specified by the
              variable name in svar. The return value of the command is empty.
              This is a near-equivalent of lreplace for sets.

       ::struct::set add svar set
              All the element of set are added to the set specified by the
              variable name in svar. The return value of the command is empty.
              This is like the method include, but for the addition of a whole
              set. If the variable named by svar does not exist it will be
              created.

       ::struct::set subtract svar set
              All the element of set are removed from the set specified by the
              variable name in svar. The return value of the command is empty.
              This is like the method exclude, but for the removal of a whole
              set.

       ::struct::set subsetof A B
              Returns a boolean value indicating if the set A is a true subset
              of or equal to the set B (true), or not (false).

REFERENCES
BUGS, IDEAS, FEEDBACK
       This document, and the package it describes, will undoubtedly contain
       bugs and other problems.  Please report such in the category struct ::
       set of the Tcllib SF Trackers
       [http://sourceforge.net/tracker/?group_id=12883].  Please also report
       any ideas for enhancements you may have for either package and/or
       documentation.

KEYWORDS
       cardinality, difference, emptiness, exclusion, inclusion, intersection,
       membership, set, symmetric difference, union

CATEGORY
       Data structures

COPYRIGHT
       Copyright (c) 2004-2008 Andreas Kupries <andreas_kupries@users.sourceforge.net>




struct                               2.2.3                      struct::set(n)
