#!/usr/bin/env python
# -*- coding: utf-8 -*-
# ---------------------------------------------------------------------
# Copyright (c) Merchise Autrement [~º/~] and Contributors
# All rights reserved.
#
# This is free software; you can do what the LICENCE file allows you to.
#
'''
Regular expressions and validation functions for several identifiers.
'''
from __future__ import (division as _py3_division,
print_function as _py3_print,
absolute_import as _py3_abs_import)
from re import compile as _regex_compile
from xoutil.eight import string_types
__all__ = ('is_valid_identifier', 'is_valid_full_identifier',
'is_valid_public_identifier',
'is_valid_slug')
# TODO: In Py3k "ña" is a valid identifier and this regex won't allow it
_IDENTIFIER_REGEX = _regex_compile('(?i)^[_a-z][\w]*$')
[docs]def is_valid_identifier(name):
'''Returns True if `name` a valid Python identifier.
.. note:: Only Python 2's version of valid identifier. This means that some
Python 3 valid identifiers are not considered valid. This helps
to keep things working the same in Python 2 and 3.
'''
return isinstance(name, string_types) and _IDENTIFIER_REGEX.match(name)
def check_identifier(name):
'''Checks if `name` a valid Python identifier.
If not, an exception is raised.
'''
if is_valid_identifier(name):
return name
else:
raise ValueError('"%s" is not a valid identifier!' % name)
_FULL_IDENTIFIER_REGEX = _regex_compile('(?i)^[_a-z][\w]*([.][_a-z][\w]*)*$')
[docs]def is_valid_full_identifier(name):
'''Returns True if `name` is a valid dotted Python identifier.
See `is_valid_identifier`:func: for what "validity" means.
'''
return (isinstance(name, string_types) and
_FULL_IDENTIFIER_REGEX.match(name))
_PUBLIC_IDENTIFIER_REGEX = _regex_compile('(?i)^[a-z][\w]*$')
[docs]def is_valid_public_identifier(name):
'''Returns True if `name` is a valid Python identifier that is deemed
public.
Convention says that any name starting with a "_" is not public.
See `is_valid_identifier`:func: for what "validity" means.
'''
return (isinstance(name, string_types) and
_PUBLIC_IDENTIFIER_REGEX.match(name))
_SLUG_REGEX = _regex_compile('(?i)^[\w]+([-][\w]+)*$')
def is_valid_slug(slug):
return isinstance(slug, string_types) and _SLUG_REGEX.match(slug)