##############################################################################
#
# Copyright (c) 2001 Zope Corporation and Contributors. All Rights Reserved.
#
# This software is subject to the provisions of the Zope Public License,
# Version 2.0 (ZPL). A copy of the ZPL should accompany this distribution.
# THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED
# WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS
# FOR A PARTICULAR PURPOSE
#
##############################################################################
"""
Advanced sort support by Oleg Broytmann <phd@@phd.pp.ru> 23 Apr 2001
eg Sort(sequence, (("akey", "nocase"), ("anotherkey", "cmp", "desc")))
$Id: SortEx.py,v 1.5.6.1 2002/09/25 15:56:05 jeremy Exp $
"""
TupleType=type(())
def sort(sequence, sort=(), _=None, mapping=0):
"""
- sequence is a sequence of objects to be sorted
- sort is a sequence of tuples (key,func,direction)
that define the sort order:
- key is the name of an attribute to sort the objects by
- func is the name of a comparison function. This parameter is
optional
allowed values:
- "cmp" -- the standard comparison function (default)
- "nocase" -- case-insensitive comparison
- "strcoll" or "locale" -- locale-aware string comparison
- "strcoll_nocase" or "locale_nocase" -- locale-aware case-insensitive
string comparison
- "xxx" -- a user-defined comparison function
- direction -- defines the sort direction for the key (optional).
(allowed values: "asc" (default) , "desc")
"""
need_sortfunc = 0
if sort:
for s in sort:
if len(s) > 1: # extended sort if there is reference to...
# ...comparison function or sort order, even if they are "cmp" and "asc"
need_sortfunc = 1
break
sortfields = sort # multi sort = key1,key2
multsort = len(sortfields) > 1 # flag: is multiple sort
if need_sortfunc:
# prepare the list of functions and sort order multipliers
sf_list = make_sortfunctions(sortfields, _)
# clean the mess a bit
if multsort: # More than one sort key.
sortfields = map(lambda x: x[0], sf_list)
else:
sort = sf_list[0][0]
elif sort:
if multsort: # More than one sort key.
sortfields = map(lambda x: x[0], sort)
else:
sort = sort[0][0]
isort=not sort
s=[]
for client in sequence:
k = None
if type(client)==TupleType and len(client)==2:
if isort: k=client[0]
v=client[1]
else:
if isort: k=client
v=client
if sort:
if multsort: # More than one sort key.
k = []
for sk in sortfields:
try:
if mapping: akey = v[sk]
else: akey = getattr(v, sk)
except (AttributeError, KeyError):
akey = None
if not basic_type(akey):
try: akey = akey()
except: pass
k.append(akey)
else: # One sort key.
try:
if mapping: k = v[sort]
else: k = getattr(v, sort)
except (AttributeError, KeyError):
k = None
if not basic_type(type(k)):
try: k = k()
except: pass
s.append((k,client))
if need_sortfunc:
by = SortBy(multsort, sf_list)
s.sort(by)
else:
s.sort()
sequence=[]
for k, client in s:
sequence.append(client)
return sequence
SortEx = sort
basic_type={type(''): 1, type(0): 1, type(0.0): 1, type(()): 1, type([]): 1,
type(None) : 1 }.has_key
def nocase(str1, str2):
return cmp(str1.lower(), str2.lower())
import sys
if sys.modules.has_key("locale"): # only if locale is already imported
from locale import strcoll
def strcoll_nocase(str1, str2):
return strcoll(str1.lower(), str2.lower())
def make_sortfunctions(sortfields, _):
"""Accepts a list of sort fields; splits every field, finds comparison
function. Returns a list of 3-tuples (field, cmp_function, asc_multplier)"""
sf_list = []
for field in sortfields:
f = list(field)
l = len(f)
if l == 1:
f.append("cmp")
f.append("asc")
elif l == 2:
f.append("asc")
elif l == 3:
pass
else:
raise SyntaxError, "sort option must contains no more than 2 fields"
f_name = f[1]
# predefined function?
if f_name == "cmp":
func = cmp # builtin
elif f_name == "nocase":
func = nocase
elif f_name in ("locale", "strcoll"):
func = strcoll
elif f_name in ("locale_nocase", "strcoll_nocase"):
func = strcoll_nocase
else: # no - look it up in the namespace
func = _.getitem(f_name, 0)
sort_order = f[2].lower()
if sort_order == "asc":
multiplier = +1
elif sort_order == "desc":
multiplier = -1
else:
raise SyntaxError, "sort oder must be either ASC or DESC"
sf_list.append((f[0], func, multiplier))
return sf_list
class SortBy:
def __init__(self, multsort, sf_list):
self.multsort = multsort
self.sf_list = sf_list
def __call__(self, o1, o2):
multsort = self.multsort
if multsort:
o1 = o1[0] # if multsort - take the first element (key list)
o2 = o2[0]
sf_list = self.sf_list
l = len(sf_list)
# assert that o1 and o2 are tuples of apropriate length
assert len(o1) == l + 1 - multsort, "%s, %d" % (o1, l + multsort)
assert len(o2) == l + 1 - multsort, "%s, %d" % (o2, l + multsort)
# now run through the list of functions in sf_list and
# compare every object in o1 and o2
for i in range(l):
# if multsort - we already extracted the key list
# if not multsort - i is 0, and the 0th element is the key
c1, c2 = o1[i], o2[i]
func, multiplier = sf_list[i][1:3]
n = func(c1, c2)
if n: return n*multiplier
# all functions returned 0 - identical sequences
return 0
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