#!/bin/env python

#Copyright ReportLab Europe Ltd. 2000-2004

#see license.txt for license details

#history http://www.reportlab.co.uk/cgi-bin/viewcvs.cgi/public/reportlab/trunk/reportlab/lib/set_ops.py

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))