Python 2.4 Compatibiity

Sets for python-2.3

In python-2.4, a builtin set type was added to python. This module provides a function to emulate that on python-2.3 by using the sets module.

set()

Create a set. If running on python 2.4+ this is the set constructor. If using python-2.3, it’s sets.Set.

frozenset()

Create a frozenset. If running on python2.4+ this is the frozenset constructor. If using python-2.3, it’s sets.ImmutableSet.

Changed in version 0.2.0: API: kitchen.pycompat24 1.0.0 Added set and frozenset

kitchen.pycompat24.sets.add_builtin_set()

If there’s no set builtin, us the sets module to make one

This function makes sure that a set and frozenset type are available in the __builtin__ namespace. Since the function checks whether set and frozenset are already present in the __builtin__ namespace and refuses to overwrite those if found, it’s safe to call this in multiple places and in scripts run under python-2.4+, where a more efficient set implementation is already present in the __builtin__ namespace.

However, since this function modifies __builtin__ there’s no need to call it more than once so you likely want to do something like this when your program loads:

myprogram/__init__.py:

from kitchen.pycompat24 import sets
builtinset.add_builtin_set()

You can then use set() and frozenset() anywhere in your code:

myprogram/compute.py:

def math_students(algebra_student_list, geometry_student_list):
    return set(algebra_student_list) union set(geometry_student_list)

Partial new style base64 interface

Implement the modern base64 interface.

Python-2.4 and above have a new API for the base64 module. This is a backport of that module for use on python-2.3.

See also

base64 for information about using the functions provided here.

kitchen.pycompat24.base64.b16decode(s, casefold=False)

Decode a Base16 encoded string.

s is the string to decode. Optional casefold is a flag specifying whether a lowercase alphabet is acceptable as input. For security purposes, the default is False.

The decoded string is returned. A TypeError is raised if s were incorrectly padded or if there are non-alphabet characters present in the string.

kitchen.pycompat24.base64.b16encode(s)

Encode a string using Base16.

s is the string to encode. The encoded string is returned.

kitchen.pycompat24.base64.b32decode(s, casefold=False, map01=None)

Decode a Base32 encoded string.

s is the string to decode. Optional casefold is a flag specifying whether a lowercase alphabet is acceptable as input. For security purposes, the default is False.

RFC 3548 allows for optional mapping of the digit 0 (zero) to the letter O (oh), and for optional mapping of the digit 1 (one) to either the letter I (eye) or letter L (el). The optional argument map01 when not None, specifies which letter the digit 1 should be mapped to (when map01 is not None, the digit 0 is always mapped to the letter O). For security purposes the default is None, so that 0 and 1 are not allowed in the input.

The decoded string is returned. A TypeError is raised if s were incorrectly padded or if there are non-alphabet characters present in the string.

kitchen.pycompat24.base64.b32encode(s)

Encode a string using Base32.

s is the string to encode. The encoded string is returned.

kitchen.pycompat24.base64.b64decode(s, altchars=None)

Decode a Base64 encoded string.

s is the string to decode. Optional altchars must be a string of at least length 2 (additional characters are ignored) which specifies the alternative alphabet used instead of the ‘+’ and ‘/’ characters.

The decoded string is returned. A TypeError is raised if s were incorrectly padded or if there are non-alphabet characters present in the string.

kitchen.pycompat24.base64.b64encode(s, altchars=None)

Encode a string using Base64.

s is the string to encode. Optional altchars must be a string of at least length 2 (additional characters are ignored) which specifies an alternative alphabet for the ‘+’ and ‘/’ characters. This allows an application to e.g. generate url or filesystem safe Base64 strings.

The encoded string is returned.

kitchen.pycompat24.base64.decode(input, output)

Decode a file.

kitchen.pycompat24.base64.decodestring(s)

Decode a string.

kitchen.pycompat24.base64.encode(input, output)

Encode a file.

kitchen.pycompat24.base64.encodestring(s)

Encode a string into multiple lines of base-64 data.

kitchen.pycompat24.base64.standard_b64decode(s)

Decode a string encoded with the standard Base64 alphabet.

s is the string to decode. The decoded string is returned. A TypeError is raised if the string is incorrectly padded or if there are non-alphabet characters present in the string.

kitchen.pycompat24.base64.standard_b64encode(s)

Encode a string using the standard Base64 alphabet.

s is the string to encode. The encoded string is returned.

kitchen.pycompat24.base64.urlsafe_b64decode(s)

Decode a string encoded with the standard Base64 alphabet.

s is the string to decode. The decoded string is returned. A TypeError is raised if the string is incorrectly padded or if there are non-alphabet characters present in the string.

The alphabet uses ‘-‘ instead of ‘+’ and ‘_’ instead of ‘/’.

kitchen.pycompat24.base64.urlsafe_b64encode(s)

Encode a string using a url-safe Base64 alphabet.

s is the string to encode. The encoded string is returned. The alphabet uses ‘-‘ instead of ‘+’ and ‘_’ instead of ‘/’.

Subprocess

See also

kitchen.pycompat27.subprocess

Kitchen includes the python-2.7 version of subprocess which has a new function, check_output(). When you import pycompat24.subprocess you will be getting the python-2.7 version of subprocess rather than the 2.4 version (where subprocess first appeared). This choice was made so that we can concentrate our efforts on keeping the single version of subprocess up to date rather than working on a 2.4 version that very few people would need specifically.