"""
This module defines the different types of terms. Terms are the kinds of
objects that can appear in a quoted/asserted triple. This includes those
that are core to RDF:
* :class:`Blank Nodes <rdflib.term.BNode>`
* :class:`URI References <rdflib.term.URIRef>`
* :class:`Literals <rdflib.term.Literal>` (which consist of a literal value,datatype and language tag)
Those that extend the RDF model into N3:
* :class:`Formulae <rdflib.graph.QuotedGraph>`
* :class:`Universal Quantifications (Variables) <rdflib.term.Variable>`
And those that are primarily for matching against 'Nodes' in the
underlying Graph:
* REGEX Expressions
* Date Ranges
* Numerical Ranges
"""
from __future__ import absolute_import
from __future__ import division
from __future__ import print_function
# from __future__ import unicode_literals
from fractions import Fraction
__all__ = [
'bind',
'Node',
'Identifier',
'URIRef',
'BNode',
'Literal',
'Variable',
'Statement',
]
import logging
logger = logging.getLogger(__name__)
import warnings
import math
import base64
import xml.dom.minidom
from datetime import date, time, datetime, timedelta
from re import sub, compile
from collections import defaultdict
from unicodedata import category
from isodate import parse_time, parse_date, parse_datetime, Duration, parse_duration, duration_isoformat
from binascii import hexlify, unhexlify
import rdflib
from six import PY2
from six import PY3
from six import b
from rdflib.compat import long_type
from six import string_types
from six import text_type
from six.moves.urllib.parse import urldefrag
from six.moves.urllib.parse import urljoin
from six.moves.urllib.parse import urlparse
skolem_genid = "/.well-known/genid/"
rdflib_skolem_genid = "/.well-known/genid/rdflib/"
skolems = {}
_invalid_uri_chars = '<>" {}|\\^`'
def _is_valid_uri(uri):
return all(map(lambda c: ord(c) > 256 or not c in _invalid_uri_chars, uri))
_lang_tag_regex = compile('^[a-zA-Z]+(?:-[a-zA-Z0-9]+)*$')
def _is_valid_langtag(tag):
return bool(_lang_tag_regex.match(tag))
def _is_valid_unicode(value):
"""
Verify that the provided value can be converted into a Python
unicode object.
"""
if isinstance(value, bytes):
coding_func, param = getattr(value, 'decode'), 'utf-8'
elif PY3:
coding_func, param = str, value
else:
coding_func, param = unicode, value
# try to convert value into unicode
try:
coding_func(param)
except UnicodeError:
return False
return True
class Node(object):
"""
A Node in the Graph.
"""
__slots__ = ()
class Identifier(Node, text_type): # allow Identifiers to be Nodes in the Graph
"""
See http://www.w3.org/2002/07/rdf-identifer-terminology/
regarding choice of terminology.
"""
__slots__ = ()
def __new__(cls, value):
return text_type.__new__(cls, value)
def eq(self, other):
"""A "semantic"/interpreted equality function,
by default, same as __eq__"""
return self.__eq__(other)
def neq(self, other):
"""A "semantic"/interpreted not equal function,
by default, same as __ne__"""
return self.__ne__(other)
def __ne__(self, other):
return not self.__eq__(other)
def __eq__(self, other):
"""
Equality for Nodes.
>>> BNode("foo")==None
False
>>> BNode("foo")==URIRef("foo")
False
>>> URIRef("foo")==BNode("foo")
False
>>> BNode("foo")!=URIRef("foo")
True
>>> URIRef("foo")!=BNode("foo")
True
>>> Variable('a')!=URIRef('a')
True
>>> Variable('a')!=Variable('a')
False
"""
if type(self) == type(other):
return text_type(self) == text_type(other)
else:
return False
def __gt__(self, other):
"""
This implements ordering for Nodes,
This tries to implement this:
http://www.w3.org/TR/sparql11-query/#modOrderBy
Variables are not included in the SPARQL list, but
they are greater than BNodes and smaller than everything else
"""
if other is None:
return True # everything bigger than None
elif type(self) == type(other):
return text_type(self) > text_type(other)
elif isinstance(other, Node):
return _ORDERING[type(self)] > _ORDERING[type(other)]
return NotImplemented
def __lt__(self, other):
if other is None:
return False # Nothing is less than None
elif type(self) == type(other):
return text_type(self) < text_type(other)
elif isinstance(other, Node):
return _ORDERING[type(self)] < _ORDERING[type(other)]
return NotImplemented
def __le__(self, other):
r = self.__lt__(other)
if r:
return True
return self == other
def __ge__(self, other):
r = self.__gt__(other)
if r:
return True
return self == other
# use parent's hash for efficiency reasons
# clashes of 'foo', URIRef('foo') and Literal('foo') are typically so rare
# that they don't justify additional overhead. Notice that even in case of
# clash __eq__ is still the fallback and very quick in those cases.
__hash__ = text_type.__hash__
class URIRef(Identifier):
"""
RDF URI Reference: http://www.w3.org/TR/rdf-concepts/#section-Graph-URIref
"""
__slots__ = ()
def __new__(cls, value, base=None):
if base is not None:
ends_in_hash = value.endswith("#")
value = urljoin(base, value, allow_fragments=1)
if ends_in_hash:
if not value.endswith("#"):
value += "#"
if not _is_valid_uri(value):
logger.warning('%s does not look like a valid URI, trying to serialize this will break.'%value)
try:
rt = text_type.__new__(cls, value)
except UnicodeDecodeError:
rt = text_type.__new__(cls, value, 'utf-8')
return rt
def toPython(self):
return text_type(self)
def n3(self, namespace_manager=None):
"""
This will do a limited check for valid URIs,
essentially just making sure that the string includes no illegal
characters (``<, >, ", {, }, |, \\, `, ^``)
:param namespace_manager: if not None, will be used to make up
a prefixed name
"""
if not _is_valid_uri(self):
raise Exception('"%s" does not look like a valid URI, I cannot serialize this as N3/Turtle. Perhaps you wanted to urlencode it?'%self)
if namespace_manager:
return namespace_manager.normalizeUri(self)
else:
return "<%s>" % self
def defrag(self):
if "#" in self:
url, frag = urldefrag(self)
return URIRef(url)
else:
return self
def __reduce__(self):
return (URIRef, (text_type(self),))
def __getnewargs__(self):
return (text_type(self), )
if PY2:
def __str__(self):
return self.encode()
def __repr__(self):
if self.__class__ is URIRef:
clsName = "rdflib.term.URIRef"
else:
clsName = self.__class__.__name__
return """%s(%s)""" % (clsName, super(URIRef, self).__repr__())
def __add__(self, other):
return self.__class__(text_type(self) + other)
def __radd__(self, other):
return self.__class__(other + text_type(self))
def __mod__(self, other):
return self.__class__(text_type(self) % other)
def de_skolemize(self):
""" Create a Blank Node from a skolem URI, in accordance
with http://www.w3.org/TR/rdf11-concepts/#section-skolemization.
This function accepts only rdflib type skolemization, to provide
a round-tripping within the system.
.. versionadded:: 4.0
"""
if isinstance(self, RDFLibGenid):
parsed_uri = urlparse("%s" % self)
return BNode(
value=parsed_uri.path[len(rdflib_skolem_genid):])
elif isinstance(self, Genid):
bnode_id = "%s" % self
if bnode_id in skolems:
return skolems[bnode_id]
else:
retval = BNode()
skolems[bnode_id] = retval
return retval
else:
raise Exception("<%s> is not a skolem URI" % self)
class Genid(URIRef):
__slots__ = ()
@staticmethod
def _is_external_skolem(uri):
if not isinstance(uri, string_types):
uri = str(uri)
parsed_uri = urlparse(uri)
gen_id = parsed_uri.path.rfind(skolem_genid)
if gen_id != 0:
return False
return True
class RDFLibGenid(Genid):
__slots__ = ()
@staticmethod
def _is_rdflib_skolem(uri):
if not isinstance(uri, string_types):
uri = str(uri)
parsed_uri = urlparse(uri)
if parsed_uri.params != "" \
or parsed_uri.query != "" \
or parsed_uri.fragment != "":
return False
gen_id = parsed_uri.path.rfind(rdflib_skolem_genid)
if gen_id != 0:
return False
return True
def _unique_id():
# Used to read: """Create a (hopefully) unique prefix"""
# now retained merely to leave interal API unchanged.
# From BNode.__new__() below ...
#
# acceptable bnode value range for RDF/XML needs to be
# something that can be serialzed as a nodeID for N3
#
# BNode identifiers must be valid NCNames" _:[A-Za-z][A-Za-z0-9]*
# http://www.w3.org/TR/2004/REC-rdf-testcases-20040210/#nodeID
return "N" # ensure that id starts with a letter
def _serial_number_generator():
"""
Generates UUID4-based but ncname-compliant identifiers.
"""
from uuid import uuid4
def _generator():
return uuid4().hex
return _generator
class BNode(Identifier):
"""
Blank Node: http://www.w3.org/TR/rdf-concepts/#section-blank-nodes
"""
__slots__ = ()
def __new__(cls, value=None,
_sn_gen=_serial_number_generator(), _prefix=_unique_id()):
"""
# only store implementations should pass in a value
"""
if value is None:
# so that BNode values do not collide with ones created with
# a different instance of this module at some other time.
node_id = _sn_gen()
value = "%s%s" % (_prefix, node_id)
else:
# TODO: check that value falls within acceptable bnode value range
# for RDF/XML needs to be something that can be serialzed
# as a nodeID for N3 ?? Unless we require these
# constraints be enforced elsewhere?
pass # assert is_ncname(text_type(value)), "BNode identifiers
# must be valid NCNames" _:[A-Za-z][A-Za-z0-9]*
# http://www.w3.org/TR/2004/REC-rdf-testcases-20040210/#nodeID
return Identifier.__new__(cls, value)
def toPython(self):
return text_type(self)
def n3(self, namespace_manager=None):
return "_:%s" % self
def __getnewargs__(self):
return (text_type(self), )
def __reduce__(self):
return (BNode, (text_type(self),))
if PY2:
def __str__(self):
return self.encode()
def __repr__(self):
if self.__class__ is BNode:
clsName = "rdflib.term.BNode"
else:
clsName = self.__class__.__name__
return """%s('%s')""" % (clsName, str(self))
def skolemize(self, authority=None, basepath=None):
""" Create a URIRef "skolem" representation of the BNode, in accordance
with http://www.w3.org/TR/rdf11-concepts/#section-skolemization
.. versionadded:: 4.0
"""
if authority is None:
authority = "http://rdlib.net/"
if basepath is None:
basepath = rdflib_skolem_genid
skolem = "%s%s" % (basepath, text_type(self))
return URIRef(urljoin(authority, skolem))
class Literal(Identifier):
__doc__ = """
RDF Literal: http://www.w3.org/TR/rdf-concepts/#section-Graph-Literal
The lexical value of the literal is the unicode object
The interpreted, datatyped value is available from .value
Language tags must be valid according to :rfc:5646
For valid XSD datatypes, the lexical form is optionally normalized
at construction time. Default behaviour is set by rdflib.NORMALIZE_LITERALS
and can be overridden by the normalize parameter to __new__
Equality and hashing of Literals are done based on the lexical form, i.e.:
>>> from rdflib.namespace import XSD
>>> Literal('01')!=Literal('1') # clear - strings differ
True
but with data-type they get normalized:
>>> Literal('01', datatype=XSD.integer)!=Literal('1', datatype=XSD.integer)
False
unless disabled:
>>> Literal('01', datatype=XSD.integer, normalize=False)!=Literal('1', datatype=XSD.integer)
True
Value based comparison is possible:
>>> Literal('01', datatype=XSD.integer).eq(Literal('1', datatype=XSD.float))
True
The eq method also provides limited support for basic python types:
>>> Literal(1).eq(1) # fine - int compatible with xsd:integer
True
>>> Literal('a').eq('b') # fine - str compatible with plain-lit
False
>>> Literal('a', datatype=XSD.string).eq('a') # fine - str compatible with xsd:string
True
>>> Literal('a').eq(1) # not fine, int incompatible with plain-lit
NotImplemented
Greater-than/less-than ordering comparisons are also done in value
space, when compatible datatypes are used. Incompatible datatypes
are ordered by DT, or by lang-tag. For other nodes the ordering
is None < BNode < URIRef < Literal
Any comparison with non-rdflib Node are "NotImplemented"
In PY2.X some stable order will be made up by python
In PY3 this is an error.
>>> from rdflib import Literal, XSD
>>> lit2006 = Literal('2006-01-01',datatype=XSD.date)
>>> lit2006.toPython()
datetime.date(2006, 1, 1)
>>> lit2006 < Literal('2007-01-01',datatype=XSD.date)
True
>>> Literal(datetime.utcnow()).datatype
rdflib.term.URIRef(u'http://www.w3.org/2001/XMLSchema#dateTime')
>>> Literal(1) > Literal(2) # by value
False
>>> Literal(1) > Literal(2.0) # by value
False
>>> Literal('1') > Literal(1) # by DT
True
>>> Literal('1') < Literal('1') # by lexical form
False
>>> Literal('a', lang='en') > Literal('a', lang='fr') # by lang-tag
False
>>> Literal(1) > URIRef('foo') # by node-type
True
The > < operators will eat this NotImplemented and either make up
an ordering (py2.x) or throw a TypeError (py3k):
>>> Literal(1).__gt__(2.0)
NotImplemented
"""
if not PY3:
__slots__ = ("language", "datatype", "value", "_language",
"_datatype", "_value")
else:
__slots__ = ("_language", "_datatype", "_value")
def __new__(cls, lexical_or_value, lang=None, datatype=None, normalize=None):
if lang == '':
lang = None # no empty lang-tags in RDF
normalize = normalize if normalize is not None else rdflib.NORMALIZE_LITERALS
if lang is not None and datatype is not None:
raise TypeError(
"A Literal can only have one of lang or datatype, "
"per http://www.w3.org/TR/rdf-concepts/#section-Graph-Literal")
if lang and not _is_valid_langtag(lang):
raise Exception("'%s' is not a valid language tag!" % lang)
if datatype:
datatype = URIRef(datatype)
value = None
if isinstance(lexical_or_value, Literal):
# create from another Literal instance
lang = lang or lexical_or_value.language
if datatype:
# override datatype
value = _castLexicalToPython(lexical_or_value, datatype)
else:
datatype = lexical_or_value.datatype
value = lexical_or_value.value
elif isinstance(lexical_or_value, string_types) or (PY3 and isinstance(lexical_or_value, bytes)):
# passed a string
# try parsing lexical form of datatyped literal
value = _castLexicalToPython(lexical_or_value, datatype)
if value is not None and normalize:
_value, _datatype = _castPythonToLiteral(value, datatype)
if _value is not None and _is_valid_unicode(_value):
lexical_or_value = _value
else:
# passed some python object
value = lexical_or_value
_value, _datatype = _castPythonToLiteral(lexical_or_value, datatype)
datatype = datatype or _datatype
if _value is not None:
lexical_or_value = _value
if datatype:
lang = None
if PY3 and isinstance(lexical_or_value, bytes):
lexical_or_value = lexical_or_value.decode('utf-8')
try:
inst = text_type.__new__(cls, lexical_or_value)
except UnicodeDecodeError:
inst = text_type.__new__(cls, lexical_or_value, 'utf-8')
inst._language = lang
inst._datatype = datatype
inst._value = value
return inst
def normalize(self):
"""
Returns a new literal with a normalised lexical representation
of this literal
>>> from rdflib import XSD
>>> Literal("01", datatype=XSD.integer, normalize=False).normalize()
rdflib.term.Literal(u'1', datatype=rdflib.term.URIRef(u'http://www.w3.org/2001/XMLSchema#integer'))
Illegal lexical forms for the datatype given are simply passed on
>>> Literal("a", datatype=XSD.integer, normalize=False)
rdflib.term.Literal(u'a', datatype=rdflib.term.URIRef(u'http://www.w3.org/2001/XMLSchema#integer'))
"""
if self.value is not None:
return Literal(self.value, datatype=self.datatype, lang=self.language)
else:
return self
@property
def value(self):
return self._value
@property
def language(self):
return self._language
@property
def datatype(self):
return self._datatype
def __reduce__(self):
return (Literal, (text_type(self), self.language, self.datatype),)
def __getstate__(self):
return (None, dict(language=self.language, datatype=self.datatype))
def __setstate__(self, arg):
_, d = arg
self._language = d["language"]
self._datatype = d["datatype"]
def __add__(self, val):
"""
>>> Literal(1) + 1
rdflib.term.Literal(u'2', datatype=rdflib.term.URIRef(u'http://www.w3.org/2001/XMLSchema#integer'))
>>> Literal("1") + "1"
rdflib.term.Literal(u'11')
"""
# if no val is supplied, return this Literal
if val is None:
return self
# convert the val to a Literal, if it isn't already one
if not isinstance(val, Literal):
val = Literal(val)
# if the datatypes are the same, just add the Python values and convert back
if self.datatype == val.datatype:
return Literal(self.toPython() + val.toPython(), self.language, datatype=self.datatype)
# if the datatypes are not the same but are both numeric, add the Python values and strip off decimal junk
# (i.e. tiny numbers (more than 17 decimal places) and trailing zeros) and return as a decimal
elif (
self.datatype in _NUMERIC_LITERAL_TYPES
and
val.datatype in _NUMERIC_LITERAL_TYPES
):
return Literal(
Decimal(
('%f' % round(Decimal(self.toPython()) + Decimal(val.toPython()), 15)).rstrip('0').rstrip('.')
),
datatype=_XSD_DECIMAL
)
# in all other cases, perform string concatenation
else:
try:
s = text_type.__add__(self, val)
except TypeError:
s = str(self.value) + str(val)
# if the original datatype is string-like, use that
if self.datatype in _STRING_LITERAL_TYPES:
new_datatype = self.datatype
# if not, use string
else:
new_datatype = _XSD_STRING
return Literal(s, self.language, datatype=new_datatype)
def __bool__(self):
"""
Is the Literal "True"
This is used for if statements, bool(literal), etc.
"""
if self.value is not None:
return bool(self.value)
return len(self) != 0
if PY2:
__nonzero__ = __bool__
def __neg__(self):
"""
>>> (- Literal(1))
rdflib.term.Literal(u'-1', datatype=rdflib.term.URIRef(u'http://www.w3.org/2001/XMLSchema#integer'))
>>> (- Literal(10.5))
rdflib.term.Literal(u'-10.5', datatype=rdflib.term.URIRef(u'http://www.w3.org/2001/XMLSchema#double'))
>>> from rdflib.namespace import XSD
>>> (- Literal("1", datatype=XSD.integer))
rdflib.term.Literal(u'-1', datatype=rdflib.term.URIRef(u'http://www.w3.org/2001/XMLSchema#integer'))
>>> (- Literal("1"))
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: Not a number; rdflib.term.Literal(u'1')
>>>
"""
if isinstance(self.value, (int, long_type, float)):
return Literal(self.value.__neg__())
else:
raise TypeError("Not a number; %s" % repr(self))
def __pos__(self):
"""
>>> (+ Literal(1))
rdflib.term.Literal(u'1', datatype=rdflib.term.URIRef(u'http://www.w3.org/2001/XMLSchema#integer'))
>>> (+ Literal(-1))
rdflib.term.Literal(u'-1', datatype=rdflib.term.URIRef(u'http://www.w3.org/2001/XMLSchema#integer'))
>>> from rdflib.namespace import XSD
>>> (+ Literal("-1", datatype=XSD.integer))
rdflib.term.Literal(u'-1', datatype=rdflib.term.URIRef(u'http://www.w3.org/2001/XMLSchema#integer'))
>>> (+ Literal("1"))
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: Not a number; rdflib.term.Literal(u'1')
"""
if isinstance(self.value, (int, long_type, float)):
return Literal(self.value.__pos__())
else:
raise TypeError("Not a number; %s" % repr(self))
def __abs__(self):
"""
>>> abs(Literal(-1))
rdflib.term.Literal(u'1', datatype=rdflib.term.URIRef(u'http://www.w3.org/2001/XMLSchema#integer'))
>>> from rdflib.namespace import XSD
>>> abs( Literal("-1", datatype=XSD.integer))
rdflib.term.Literal(u'1', datatype=rdflib.term.URIRef(u'http://www.w3.org/2001/XMLSchema#integer'))
>>> abs(Literal("1"))
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: Not a number; rdflib.term.Literal(u'1')
"""
if isinstance(self.value, (int, long_type, float)):
return Literal(self.value.__abs__())
else:
raise TypeError("Not a number; %s" % repr(self))
def __invert__(self):
"""
>>> ~(Literal(-1))
rdflib.term.Literal(u'0', datatype=rdflib.term.URIRef(u'http://www.w3.org/2001/XMLSchema#integer'))
>>> from rdflib.namespace import XSD
>>> ~( Literal("-1", datatype=XSD.integer))
rdflib.term.Literal(u'0', datatype=rdflib.term.URIRef(u'http://www.w3.org/2001/XMLSchema#integer'))
Not working:
>>> ~(Literal("1"))
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: Not a number; rdflib.term.Literal(u'1')
"""
if isinstance(self.value, (int, long_type, float)):
return Literal(self.value.__invert__())
else:
raise TypeError("Not a number; %s" % repr(self))
def __gt__(self, other):
"""
This implements ordering for Literals,
the other comparison methods delegate here
This tries to implement this:
http://www.w3.org/TR/sparql11-query/#modOrderBy
In short, Literals with compatible data-types are ordered in value
space, i.e.
>>> from rdflib import XSD
>>> Literal(1) > Literal(2) # int/int
False
>>> Literal(2.0) > Literal(1) # double/int
True
>>> from decimal import Decimal
>>> Literal(Decimal("3.3")) > Literal(2.0) # decimal/double
True
>>> Literal(Decimal("3.3")) < Literal(4.0) # decimal/double
True
>>> Literal('b') > Literal('a') # plain lit/plain lit
True
>>> Literal('b') > Literal('a', datatype=XSD.string) # plain lit/xsd:str
True
Incompatible datatype mismatches ordered by DT
>>> Literal(1) > Literal("2") # int>string
False
Langtagged literals by lang tag
>>> Literal("a", lang="en") > Literal("a", lang="fr")
False
"""
if other is None:
return True # Everything is greater than None
if isinstance(other, Literal):
if self.datatype in _NUMERIC_LITERAL_TYPES and \
other.datatype in _NUMERIC_LITERAL_TYPES:
return self.value > other.value
# plain-literals and xsd:string literals
# are "the same"
dtself = self.datatype or _XSD_STRING
dtother = other.datatype or _XSD_STRING
if dtself != dtother:
if rdflib.DAWG_LITERAL_COLLATION:
return NotImplemented
else:
return dtself > dtother
if self.language != other.language:
if not self.language:
return False
elif not other.language:
return True
else:
return self.language > other.language
if self.value is not None and other.value is not None:
if type(self.value) in _TOTAL_ORDER_CASTERS:
caster = _TOTAL_ORDER_CASTERS[type(self.value)]
return caster(self.value) > caster(other.value)
try:
return self.value > other.value
except TypeError:
pass
if text_type(self) != text_type(other):
return text_type(self) > text_type(other)
# same language, same lexical form, check real dt
# plain-literals come before xsd:string!
if self.datatype != other.datatype:
if not self.datatype:
return False
elif not other.datatype:
return True
else:
return self.datatype > other.datatype
return False # they are the same
elif isinstance(other, Node):
return True # Literal are the greatest!
else:
return NotImplemented # we can only compare to nodes
def __lt__(self, other):
if other is None:
return False # Nothing is less than None
if isinstance(other, Literal):
try:
return not self.__gt__(other) and not self.eq(other)
except TypeError:
return NotImplemented
if isinstance(other, Node):
return False # all nodes are less-than Literals
return NotImplemented
def __le__(self, other):
"""
>>> from rdflib.namespace import XSD
>>> Literal('2007-01-01T10:00:00', datatype=XSD.dateTime
... ) <= Literal('2007-01-01T10:00:00', datatype=XSD.dateTime)
True
"""
r = self.__lt__(other)
if r:
return True
try:
return self.eq(other)
except TypeError:
return NotImplemented
def __ge__(self, other):
r = self.__gt__(other)
if r:
return True
try:
return self.eq(other)
except TypeError:
return NotImplemented
def _comparable_to(self, other):
"""
Helper method to decide which things are meaningful to
rich-compare with this literal
"""
if isinstance(other, Literal):
if (self.datatype and other.datatype):
# two datatyped literals
if not self.datatype in XSDToPython or not other.datatype in XSDToPython:
# non XSD DTs must match
if self.datatype != other.datatype:
return False
else:
# xsd:string may be compared with plain literals
if not (self.datatype == _XSD_STRING and not other.datatype) or \
(other.datatype == _XSD_STRING and not self.datatype):
return False
# if given lang-tag has to be case insensitive equal
if (self.language or "").lower() != (other.language or "").lower():
return False
return True
def __hash__(self):
"""
>>> from rdflib.namespace import XSD
>>> a = {Literal('1', datatype=XSD.integer):'one'}
>>> Literal('1', datatype=XSD.double) in a
False
"Called for the key object for dictionary operations,
and by the built-in function hash(). Should return
a 32-bit integer usable as a hash value for
dictionary operations. The only required property
is that objects which compare equal have the same
hash value; it is advised to somehow mix together
(e.g., using exclusive or) the hash values for the
components of the object that also play a part in
comparison of objects." -- 3.4.1 Basic customization (Python)
"Two literals are equal if and only if all of the following hold:
* The strings of the two lexical forms compare equal, character by
character.
* Either both or neither have language tags.
* The language tags, if any, compare equal.
* Either both or neither have datatype URIs.
* The two datatype URIs, if any, compare equal, character by
character."
-- 6.5.1 Literal Equality (RDF: Concepts and Abstract Syntax)
"""
# don't use super()... for efficiency reasons, see Identifier.__hash__
res = text_type.__hash__(self)
if self.language:
res ^= hash(self.language.lower())
if self.datatype:
res ^= hash(self.datatype)
return res
def __eq__(self, other):
"""
Literals are only equal to other literals.
"Two literals are equal if and only if all of the following hold:
* The strings of the two lexical forms compare equal, character by character.
* Either both or neither have language tags.
* The language tags, if any, compare equal.
* Either both or neither have datatype URIs.
* The two datatype URIs, if any, compare equal, character by character."
-- 6.5.1 Literal Equality (RDF: Concepts and Abstract Syntax)
>>> Literal("1", datatype=URIRef("foo")) == Literal("1", datatype=URIRef("foo"))
True
>>> Literal("1", datatype=URIRef("foo")) == Literal("1", datatype=URIRef("foo2"))
False
>>> Literal("1", datatype=URIRef("foo")) == Literal("2", datatype=URIRef("foo"))
False
>>> Literal("1", datatype=URIRef("foo")) == "asdf"
False
>>> from rdflib import XSD
>>> Literal('2007-01-01', datatype=XSD.date) == Literal('2007-01-01', datatype=XSD.date)
True
>>> Literal('2007-01-01', datatype=XSD.date) == date(2007, 1, 1)
False
>>> Literal("one", lang="en") == Literal("one", lang="en")
True
>>> Literal("hast", lang='en') == Literal("hast", lang='de')
False
>>> Literal("1", datatype=XSD.integer) == Literal(1)
True
>>> Literal("1", datatype=XSD.integer) == Literal("01", datatype=XSD.integer)
True
"""
if self is other:
return True
if other is None:
return False
if isinstance(other, Literal):
return self.datatype == other.datatype \
and (self.language.lower() if self.language else None) == (other.language.lower() if other.language else None) \
and text_type.__eq__(self, other)
return False
def eq(self, other):
"""
Compare the value of this literal with something else
Either, with the value of another literal
comparisons are then done in literal "value space",
and according to the rules of XSD subtype-substitution/type-promotion
OR, with a python object:
basestring objects can be compared with plain-literals,
or those with datatype xsd:string
bool objects with xsd:boolean
a int, long or float with numeric xsd types
isodate date,time,datetime objects with xsd:date,xsd:time or xsd:datetime
Any other operations returns NotImplemented
"""
if isinstance(other, Literal):
if self.datatype in _NUMERIC_LITERAL_TYPES \
and other.datatype in _NUMERIC_LITERAL_TYPES:
if self.value is not None and other.value is not None:
return self.value == other.value
else:
if text_type.__eq__(self, other):
return True
raise TypeError(
'I cannot know that these two lexical forms do not map to the same value: %s and %s' % (self, other))
if (self.language or "").lower() != (other.language or "").lower():
return False
dtself = self.datatype or _XSD_STRING
dtother = other.datatype or _XSD_STRING
if (dtself == _XSD_STRING and dtother == _XSD_STRING):
# string/plain literals, compare on lexical form
return text_type.__eq__(self, other)
if dtself != dtother:
if rdflib.DAWG_LITERAL_COLLATION:
raise TypeError("I don't know how to compare literals with datatypes %s and %s" % (
self.datatype, other.datatype))
else:
return False
# matching non-string DTs now - do we compare values or
# lexical form first? comparing two ints is far quicker -
# maybe there are counter examples
if self.value is not None and other.value is not None:
if self.datatype in (_RDF_XMLLITERAL, _RDF_HTMLLITERAL):
return _isEqualXMLNode(self.value, other.value)
return self.value == other.value
else:
if text_type.__eq__(self, other):
return True
if self.datatype == _XSD_STRING:
return False # string value space=lexical space
# matching DTs, but not matching, we cannot compare!
raise TypeError(
'I cannot know that these two lexical forms do not map to the same value: %s and %s' % (self, other))
elif isinstance(other, Node):
return False # no non-Literal nodes are equal to a literal
elif isinstance(other, string_types):
# only plain-literals can be directly compared to strings
# TODO: Is "blah"@en eq "blah" ?
if self.language is not None:
return False
if (self.datatype == _XSD_STRING or self.datatype is None):
return text_type(self) == other
elif isinstance(other, (int, long_type, float)):
if self.datatype in _NUMERIC_LITERAL_TYPES:
return self.value == other
elif isinstance(other, (date, datetime, time)):
if self.datatype in (_XSD_DATETIME, _XSD_DATE, _XSD_TIME):
return self.value == other
elif isinstance(other, (timedelta, Duration)):
if self.datatype in (_XSD_DURATION, _XSD_DAYTIMEDURATION, _XSD_YEARMONTHDURATION):
return self.value == other
elif isinstance(other, bool):
if self.datatype == _XSD_BOOLEAN:
return self.value == other
return NotImplemented
def neq(self, other):
return not self.eq(other)
def n3(self, namespace_manager=None):
r'''
Returns a representation in the N3 format.
Examples::
>>> Literal("foo").n3()
u'"foo"'
Strings with newlines or triple-quotes::
>>> Literal("foo\nbar").n3()
u'"""foo\nbar"""'
>>> Literal("''\'").n3()
u'"\'\'\'"'
>>> Literal('"""').n3()
u'"\\"\\"\\""'
Language::
>>> Literal("hello", lang="en").n3()
u'"hello"@en'
Datatypes::
>>> Literal(1).n3()
u'"1"^^<http://www.w3.org/2001/XMLSchema#integer>'
>>> Literal(1.0).n3()
u'"1.0"^^<http://www.w3.org/2001/XMLSchema#double>'
>>> Literal(True).n3()
u'"true"^^<http://www.w3.org/2001/XMLSchema#boolean>'
Datatype and language isn't allowed (datatype takes precedence)::
>>> Literal(1, lang="en").n3()
u'"1"^^<http://www.w3.org/2001/XMLSchema#integer>'
Custom datatype::
>>> footype = URIRef("http://example.org/ns#foo")
>>> Literal("1", datatype=footype).n3()
u'"1"^^<http://example.org/ns#foo>'
Passing a namespace-manager will use it to abbreviate datatype URIs:
>>> from rdflib import Graph
>>> Literal(1).n3(Graph().namespace_manager)
u'"1"^^xsd:integer'
'''
if namespace_manager:
return self._literal_n3(qname_callback=namespace_manager.normalizeUri)
else:
return self._literal_n3()
def _literal_n3(self, use_plain=False, qname_callback=None):
'''
Using plain literal (shorthand) output::
>>> from rdflib.namespace import XSD
>>> Literal(1)._literal_n3(use_plain=True)
u'1'
>>> Literal(1.0)._literal_n3(use_plain=True)
u'1e+00'
>>> Literal(1.0, datatype=XSD.decimal)._literal_n3(use_plain=True)
u'1.0'
>>> Literal(1.0, datatype=XSD.float)._literal_n3(use_plain=True)
u'"1.0"^^<http://www.w3.org/2001/XMLSchema#float>'
>>> Literal("foo", datatype=XSD.string)._literal_n3(
... use_plain=True)
u'"foo"^^<http://www.w3.org/2001/XMLSchema#string>'
>>> Literal(True)._literal_n3(use_plain=True)
u'true'
>>> Literal(False)._literal_n3(use_plain=True)
u'false'
>>> Literal(1.91)._literal_n3(use_plain=True)
u'1.91e+00'
Only limited precision available for floats:
>>> Literal(0.123456789)._literal_n3(use_plain=True)
u'1.234568e-01'
>>> Literal('0.123456789',
... datatype=XSD.decimal)._literal_n3(use_plain=True)
u'0.123456789'
Using callback for datatype QNames::
>>> Literal(1)._literal_n3(
... qname_callback=lambda uri: "xsd:integer")
u'"1"^^xsd:integer'
'''
if use_plain and self.datatype in _PLAIN_LITERAL_TYPES:
if self.value is not None:
# If self is inf or NaN, we need a datatype
# (there is no plain representation)
if self.datatype in _NUMERIC_INF_NAN_LITERAL_TYPES:
try:
v = float(self)
if math.isinf(v) or math.isnan(v):
return self._literal_n3(False, qname_callback)
except ValueError:
return self._literal_n3(False, qname_callback)
# this is a bit of a mess -
# in py >=2.6 the string.format function makes this easier
# we try to produce "pretty" output
if self.datatype == _XSD_DOUBLE:
return sub("\\.?0*e", "e", u'%e' % float(self))
elif self.datatype == _XSD_DECIMAL:
s = '%s' % self
if '.' not in s:
s += '.0'
return s
elif self.datatype == _XSD_BOOLEAN:
return (u'%s' % self).lower()
else:
return u'%s' % self
encoded = self._quote_encode()
datatype = self.datatype
quoted_dt = None
if datatype:
if qname_callback:
quoted_dt = qname_callback(datatype)
if not quoted_dt:
quoted_dt = "<%s>" % datatype
if datatype in _NUMERIC_INF_NAN_LITERAL_TYPES:
try:
v = float(self)
if math.isinf(v):
# py string reps: float: 'inf', Decimal: 'Infinity"
# both need to become "INF" in xsd datatypes
encoded = encoded.replace('inf', 'INF').replace(
'Infinity', 'INF')
if math.isnan(v):
encoded = encoded.replace('nan', 'NaN')
except ValueError:
# if we can't cast to float something is wrong, but we can
# still serialize. Warn user about it
warnings.warn("Serializing weird numerical %r" % self)
language = self.language
if language:
return '%s@%s' % (encoded, language)
elif datatype:
return '%s^^%s' % (encoded, quoted_dt)
else:
return '%s' % encoded
def _quote_encode(self):
# This simpler encoding doesn't work; a newline gets encoded as "\\n",
# which is ok in sourcecode, but we want "\n".
# encoded = self.encode('unicode-escape').replace(
# '\\', '\\\\').replace('"','\\"')
# encoded = self.replace.replace('\\', '\\\\').replace('"','\\"')
# NOTE: Could in theory chose quotes based on quotes appearing in the
# string, i.e. '"' and "'", but N3/turtle doesn't allow "'"(?).
if "\n" in self:
# Triple quote this string.
encoded = self.replace('\\', '\\\\')
if '"""' in self:
# is this ok?
encoded = encoded.replace('"""', '\\"\\"\\"')
if encoded[-1] == '"' and encoded[-2] != '\\':
encoded = encoded[:-1] + '\\' + '"'
return '"""%s"""' % encoded.replace('\r', '\\r')
else:
return '"%s"' % self.replace(
'\n', '\\n').replace(
'\\', '\\\\').replace(
'"', '\\"').replace(
'\r', '\\r')
if PY2:
def __str__(self):
return self.encode()
def __repr__(self):
args = [super(Literal, self).__repr__()]
if self.language is not None:
args.append("lang=%s" % repr(self.language))
if self.datatype is not None:
args.append("datatype=%s" % repr(self.datatype))
if self.__class__ == Literal:
clsName = "rdflib.term.Literal"
else:
clsName = self.__class__.__name__
return """%s(%s)""" % (clsName, ", ".join(args))
def toPython(self):
"""
Returns an appropriate python datatype derived from this RDF Literal
"""
if self.value is not None:
return self.value
return self
def _parseXML(xmlstring):
if PY2:
xmlstring = xmlstring.encode('utf-8')
retval = xml.dom.minidom.parseString(
"<rdflibtoplevelelement>%s</rdflibtoplevelelement>" % xmlstring)
retval.normalize()
return retval
def _parseHTML(htmltext):
try:
import html5lib
parser = html5lib.HTMLParser(
tree=html5lib.treebuilders.getTreeBuilder("dom"))
retval = parser.parseFragment(htmltext)
retval.normalize()
return retval
except ImportError:
raise ImportError(
"HTML5 parser not available. Try installing" +
" html5lib <http://code.google.com/p/html5lib>")
def _writeXML(xmlnode):
if isinstance(xmlnode, xml.dom.minidom.DocumentFragment):
d = xml.dom.minidom.Document()
d.childNodes += xmlnode.childNodes
xmlnode = d
s = xmlnode.toxml('utf-8')
# for clean round-tripping, remove headers -- I have great and
# specific worries that this will blow up later, but this margin
# is too narrow to contain them
if s.startswith(b('<?xml version="1.0" encoding="utf-8"?>')):
s = s[38:]
if s.startswith(b('<rdflibtoplevelelement>')):
s = s[23:-24]
if s == b('<rdflibtoplevelelement/>'):
s = b('')
return s
def _unhexlify(value):
# In Python 3.2, unhexlify does not support str (only bytes)
if PY3 and isinstance(value, str):
value = value.encode()
return unhexlify(value)
def _parseBoolean(value):
true_accepted_values = ['1', 'true']
false_accepted_values = ['0', 'false']
new_value = value.lower()
if new_value in true_accepted_values:
return True
if new_value not in false_accepted_values:
warnings.warn('Parsing weird boolean, % r does not map to True or False' % value, category = DeprecationWarning)
return False
# Cannot import Namespace/XSD because of circular dependencies
_XSD_PFX = 'http://www.w3.org/2001/XMLSchema#'
_RDF_PFX = 'http://www.w3.org/1999/02/22-rdf-syntax-ns#'
_RDF_XMLLITERAL = URIRef(_RDF_PFX + 'XMLLiteral')
_RDF_HTMLLITERAL = URIRef(_RDF_PFX + 'HTML')
_XSD_STRING = URIRef(_XSD_PFX + 'string')
_XSD_FLOAT = URIRef(_XSD_PFX + 'float')
_XSD_DOUBLE = URIRef(_XSD_PFX + 'double')
_XSD_DECIMAL = URIRef(_XSD_PFX + 'decimal')
_XSD_INTEGER = URIRef(_XSD_PFX + 'integer')
_XSD_BOOLEAN = URIRef(_XSD_PFX + 'boolean')
_XSD_DATETIME = URIRef(_XSD_PFX + 'dateTime')
_XSD_DATE = URIRef(_XSD_PFX + 'date')
_XSD_TIME = URIRef(_XSD_PFX + 'time')
_XSD_DURATION = URIRef(_XSD_PFX + 'duration')
_XSD_DAYTIMEDURATION = URIRef(_XSD_PFX + 'dayTimeDuration')
_XSD_YEARMONTHDURATION = URIRef(_XSD_PFX + 'yearMonthDuration')
_OWL_RATIONAL = URIRef('http://www.w3.org/2002/07/owl#rational')
_XSD_HEXBINARY = URIRef(_XSD_PFX + 'hexBinary')
# TODO: gYearMonth, gYear, gMonthDay, gDay, gMonth
_NUMERIC_LITERAL_TYPES = (
_XSD_INTEGER,
_XSD_DECIMAL,
_XSD_DOUBLE,
URIRef(_XSD_PFX + 'float'),
URIRef(_XSD_PFX + 'byte'),
URIRef(_XSD_PFX + 'int'),
URIRef(_XSD_PFX + 'long'),
URIRef(_XSD_PFX + 'negativeInteger'),
URIRef(_XSD_PFX + 'nonNegativeInteger'),
URIRef(_XSD_PFX + 'nonPositiveInteger'),
URIRef(_XSD_PFX + 'positiveInteger'),
URIRef(_XSD_PFX + 'short'),
URIRef(_XSD_PFX + 'unsignedByte'),
URIRef(_XSD_PFX + 'unsignedInt'),
URIRef(_XSD_PFX + 'unsignedLong'),
URIRef(_XSD_PFX + 'unsignedShort'),
)
# these have "native" syntax in N3/SPARQL
_PLAIN_LITERAL_TYPES = (
_XSD_INTEGER,
_XSD_BOOLEAN,
_XSD_DOUBLE,
_XSD_DECIMAL,
_OWL_RATIONAL
)
# these have special INF and NaN XSD representations
_NUMERIC_INF_NAN_LITERAL_TYPES = (
URIRef(_XSD_PFX + 'float'),
_XSD_DOUBLE,
_XSD_DECIMAL,
)
# the following types need special treatment for reasonable sorting because
# certain instances can't be compared to each other. We treat this by
# partitioning and then sorting within those partitions.
_TOTAL_ORDER_CASTERS = {
datetime: lambda value: (
# naive vs. aware
value.tzinfo is not None and value.tzinfo.utcoffset(value) is not None,
value
),
time: lambda value: (
# naive vs. aware
value.tzinfo is not None and value.tzinfo.utcoffset(None) is not None,
value
),
xml.dom.minidom.Document: lambda value: value.toxml(),
}
_STRING_LITERAL_TYPES = (
_XSD_STRING,
_RDF_XMLLITERAL,
_RDF_HTMLLITERAL,
URIRef(_XSD_PFX + 'normalizedString'),
URIRef(_XSD_PFX + 'token')
)
def _py2literal(obj, pType, castFunc, dType):
if castFunc:
return castFunc(obj), dType
elif dType:
return obj, dType
else:
return obj, None
def _castPythonToLiteral(obj, datatype):
"""
Casts a tuple of a python type and a special datatype URI to a tuple of the lexical value and a
datatype URI (or None)
"""
for (pType, dType), castFunc in _SpecificPythonToXSDRules:
if isinstance(obj, pType) and dType == datatype:
return _py2literal(obj, pType, castFunc, dType)
for pType, (castFunc, dType) in _GenericPythonToXSDRules:
if isinstance(obj, pType):
return _py2literal(obj, pType, castFunc, dType)
return obj, None # TODO: is this right for the fall through case?
from decimal import Decimal
# Mappings from Python types to XSD datatypes and back (borrowed from sparta)
# datetime instances are also instances of date... so we need to order these.
# SPARQL/Turtle/N3 has shortcuts for integer, double, decimal
# python has only float - to be in tune with sparql/n3/turtle
# we default to XSD.double for float literals
# python ints are promoted to longs when overflowing
# python longs have no limit
# both map to the abstract integer type,
# rather than some concrete bit-limited datatype
_GenericPythonToXSDRules = [
(string_types, (None, None)),
(float, (None, _XSD_DOUBLE)),
(bool, (lambda i:str(i).lower(), _XSD_BOOLEAN)),
(int, (None, _XSD_INTEGER)),
(long_type, (None, _XSD_INTEGER)),
(Decimal, (None, _XSD_DECIMAL)),
(datetime, (lambda i:i.isoformat(), _XSD_DATETIME)),
(date, (lambda i:i.isoformat(), _XSD_DATE)),
(time, (lambda i:i.isoformat(), _XSD_TIME)),
(Duration, (lambda i:duration_isoformat(i), _XSD_DURATION)),
(timedelta, (lambda i:duration_isoformat(i), _XSD_DAYTIMEDURATION)),
(xml.dom.minidom.Document, (_writeXML, _RDF_XMLLITERAL)),
# this is a bit dirty - by accident the html5lib parser produces
# DocumentFragments, and the xml parser Documents, letting this
# decide what datatype to use makes roundtripping easier, but it a
# bit random
(xml.dom.minidom.DocumentFragment, (_writeXML, _RDF_HTMLLITERAL)),
(Fraction, (None, _OWL_RATIONAL))
]
_SpecificPythonToXSDRules = [
((string_types, _XSD_HEXBINARY), hexlify),
]
if PY3:
_SpecificPythonToXSDRules.append(((bytes, _XSD_HEXBINARY), hexlify))
XSDToPython = {
None: None, # plain literals map directly to value space
URIRef(_XSD_PFX + 'time'): parse_time,
URIRef(_XSD_PFX + 'date'): parse_date,
URIRef(_XSD_PFX + 'gYear'): parse_date,
URIRef(_XSD_PFX + 'gYearMonth'): parse_date,
URIRef(_XSD_PFX + 'dateTime'): parse_datetime,
URIRef(_XSD_PFX + 'duration'): parse_duration,
URIRef(_XSD_PFX + 'dayTimeDuration'): parse_duration,
URIRef(_XSD_PFX + 'yearMonthDuration'): parse_duration,
URIRef(_XSD_PFX + 'hexBinary'): _unhexlify,
URIRef(_XSD_PFX + 'string'): None,
URIRef(_XSD_PFX + 'normalizedString'): None,
URIRef(_XSD_PFX + 'token'): None,
URIRef(_XSD_PFX + 'language'): None,
URIRef(_XSD_PFX + 'boolean'): _parseBoolean,
URIRef(_XSD_PFX + 'decimal'): Decimal,
URIRef(_XSD_PFX + 'integer'): long_type,
URIRef(_XSD_PFX + 'nonPositiveInteger'): int,
URIRef(_XSD_PFX + 'long'): long_type,
URIRef(_XSD_PFX + 'nonNegativeInteger'): int,
URIRef(_XSD_PFX + 'negativeInteger'): int,
URIRef(_XSD_PFX + 'int'): long_type,
URIRef(_XSD_PFX + 'unsignedLong'): long_type,
URIRef(_XSD_PFX + 'positiveInteger'): int,
URIRef(_XSD_PFX + 'short'): int,
URIRef(_XSD_PFX + 'unsignedInt'): long_type,
URIRef(_XSD_PFX + 'byte'): int,
URIRef(_XSD_PFX + 'unsignedShort'): int,
URIRef(_XSD_PFX + 'unsignedByte'): int,
URIRef(_XSD_PFX + 'float'): float,
URIRef(_XSD_PFX + 'double'): float,
URIRef(_XSD_PFX + 'base64Binary'): lambda s: base64.b64decode(s),
URIRef(_XSD_PFX + 'anyURI'): None,
_RDF_XMLLITERAL: _parseXML,
_RDF_HTMLLITERAL: _parseHTML
}
_toPythonMapping = {}
_toPythonMapping.update(XSDToPython)
def _castLexicalToPython(lexical, datatype):
"""
Map a lexical form to the value-space for the given datatype
:returns: a python object for the value or ``None``
"""
convFunc = _toPythonMapping.get(datatype, False)
if convFunc:
try:
return convFunc(lexical)
except:
# not a valid lexical representation for this dt
return None
elif convFunc is None:
# no conv func means 1-1 lexical<->value-space mapping
try:
return text_type(lexical)
except UnicodeDecodeError:
return text_type(lexical, 'utf-8')
else:
# no convFunc - unknown data-type
return None
def bind(datatype, pythontype, constructor=None, lexicalizer=None, datatype_specific=False):
"""
register a new datatype<->pythontype binding
:param constructor: an optional function for converting lexical forms
into a Python instances, if not given the pythontype
is used directly
:param lexicalizer: an optional function for converting python objects to
lexical form, if not given object.__str__ is used
:param datatype_specific: makes the lexicalizer function be accessible
from the pair (pythontype, datatype) if set to True
or from the pythontype otherwise. False by default
"""
if datatype_specific and datatype is None:
raise Exception("No datatype given for a datatype-specific binding")
if datatype in _toPythonMapping:
logger.warning("datatype '%s' was already bound. Rebinding." %
datatype)
if constructor is None:
constructor = pythontype
_toPythonMapping[datatype] = constructor
if datatype_specific:
_SpecificPythonToXSDRules.append(((pythontype, datatype), lexicalizer))
else:
_GenericPythonToXSDRules.append((pythontype, (lexicalizer, datatype)))
class Variable(Identifier):
"""
A Variable - this is used for querying, or in Formula aware
graphs, where Variables can stored in the graph
"""
__slots__ = ()
def __new__(cls, value):
if len(value) == 0:
raise Exception(
"Attempted to create variable with empty string as name!")
if value[0] == '?':
value = value[1:]
return text_type.__new__(cls, value)
def __repr__(self):
if self.__class__ is Variable:
clsName = "rdflib.term.Variable"
else:
clsName = self.__class__.__name__
return """%s(%s)""" % (clsName, super(Variable, self).__repr__())
def toPython(self):
return "?%s" % self
def n3(self, namespace_manager=None):
return "?%s" % self
def __reduce__(self):
return (Variable, (text_type(self),))
class Statement(Node, tuple):
def __new__(cls, triple, context):
subject, predicate, object = triple
warnings.warn(
"Class Statement is deprecated, and will be removed in " +
"the future. If you use this please let rdflib-dev know!",
category=DeprecationWarning, stacklevel=2)
return tuple.__new__(cls, ((subject, predicate, object), context))
def __reduce__(self):
return (Statement, (self[0], self[1]))
def toPython(self):
return (self[0], self[1])
# Nodes are ordered like this
# See http://www.w3.org/TR/sparql11-query/#modOrderBy
# we leave "space" for more subclasses of Node elsewhere
# default-dict to grazefully fail for new subclasses
_ORDERING = defaultdict(int)
_ORDERING.update({
BNode: 10,
Variable: 20,
URIRef: 30,
Literal: 40
})
def _isEqualXMLNode(node, other):
from xml.dom.minidom import Node
def recurse():
# Recursion through the children
# In Python2, the semantics of 'map' is such that the check on
# length would be unnecessary. In Python 3,
# the semantics of map has changed (why, oh why???) and the check
# for the length becomes necessary...
if len(node.childNodes) != len(other.childNodes):
return False
for (nc, oc) in map(
lambda x, y: (x, y), node.childNodes, other.childNodes):
if not _isEqualXMLNode(nc, oc):
return False
# if we got here then everything is fine:
return True
if node is None or other is None:
return False
if node.nodeType != other.nodeType:
return False
if node.nodeType in [Node.DOCUMENT_NODE, Node.DOCUMENT_FRAGMENT_NODE]:
return recurse()
elif node.nodeType == Node.ELEMENT_NODE:
# Get the basics right
if not (node.tagName == other.tagName and
node.namespaceURI == other.namespaceURI):
return False
# Handle the (namespaced) attributes; the namespace setting key
# should be ignored, though
# Note that the minidom orders the keys already, so we do not have
# to worry about that, which is a bonus...
n_keys = [
k for k in node.attributes.keysNS()
if k[0] != 'http://www.w3.org/2000/xmlns/']
o_keys = [
k for k in other.attributes.keysNS()
if k[0] != 'http://www.w3.org/2000/xmlns/']
if len(n_keys) != len(o_keys):
return False
for k in n_keys:
if not (k in o_keys
and node.getAttributeNS(k[0], k[1]) ==
other.getAttributeNS(k[0], k[1])):
return False
# if we got here, the attributes are all right, we can go down
# the tree recursively
return recurse()
elif node.nodeType in [
Node.TEXT_NODE, Node.COMMENT_NODE, Node.CDATA_SECTION_NODE,
Node.NOTATION_NODE]:
return node.data == other.data
elif node.nodeType == Node.PROCESSING_INSTRUCTION_NODE:
return node.data == other.data and node.target == other.target
elif node.nodeType == Node.ENTITY_NODE:
return node.nodeValue == other.nodeValue
elif node.nodeType == Node.DOCUMENT_TYPE_NODE:
return node.publicId == other.publicId \
and node.systemId == other.system.Id
else:
# should not happen, in fact
raise Exception(
'I dont know how to compare XML Node type: %s' % node.nodeType)
if __name__ == '__main__':
import doctest
doctest.testmod()