#!/bin/env python

#copyright ReportLab Inc. 2000

#see license.txt for license details

#history http://cvs.sourceforge.net/cgi-bin/cvsweb.cgi/reportlab/lib/set_ops.py?cvsroot=reportlab

#$Header: /tmp/reportlab/reportlab/lib/set_ops.py,v 1.1 2003/06/10 09:59:06 rgbecker Exp $

import types

import string

def __set_coerce(t, S):

    if t is types.ListType:

        return list(S)

    elif t is types.TupleType:

        return tuple(S)

    elif t is types.StringType:

        return string.join(S, '')

    return S

def unique(seq):

    result = []

    for i in seq:

        if i not in result:

            result.append(i)

    return __set_coerce(type(seq), result)

def intersect(seq1, seq2):

    result = []

    if type(seq1) != type(seq2) and type(seq2) == types.StringType: seq2 = list(seq2)

    for i in seq1:

        if i in seq2 and i not in result: result.append(i)

    return __set_coerce(type(seq1), result)

def union(seq1, seq2):

    if type(seq1) == type(seq2):

        return unique(seq1 + seq2)

    if type(seq1) == types.ListType or type(seq2) == types.ListType:

        return unique(list(seq1) + list(seq2))

    if type(seq1) == types.TupleType or type(seq2) == types.TupleType:

        return unique(tuple(seq1) + tuple(seq2))

    return unique(list(seq1) + list(seq2))