def parse_primary(self):
token = self.stream.current
if token.type == 'name':
if token.value in ('true', 'false', 'True', 'False'):
node = nodes.Const(token.value in ('true', 'True'),
lineno=token.lineno)
elif token.value in ('none', 'None'):
node = nodes.Const(None, lineno=token.lineno)
else:
node = nodes.Name(token.value, 'load', lineno=token.lineno)
next(self.stream)
elif token.type == 'string':
next(self.stream)
buf = [token.value]
lineno = token.lineno
while self.stream.current.type == 'string':
buf.append(self.stream.current.value)
next(self.stream)
node = nodes.Const(''.join(buf), lineno=lineno)
elif token.type in ('integer', 'float'):
next(self.stream)
node = nodes.Const(token.value, lineno=token.lineno)
elif token.type == 'lparen':
next(self.stream)
node = self.parse_tuple(explicit_parentheses=True)
self.stream.expect('rparen')
elif token.type == 'lbracket':
node = self.parse_list()
elif token.type == 'lbrace':
node = self.parse_dict()
else:
self.fail("unexpected '%s'" % describe_token(token), token.lineno)
return node
def parse_primary(self):
token = self.stream.current
if token.type == 'name':
if token.value in ('true', 'false', 'True', 'False'):
node = nodes.Const(token.value in ('true', 'True'),
lineno=token.lineno)
elif token.value in ('none', 'None'):
node = nodes.Const(None, lineno=token.lineno)
else:
node = nodes.Name(token.value, 'load', lineno=token.lineno)
next(self.stream)
elif token.type == 'string':
next(self.stream)
buf = [token.value]
lineno = token.lineno
while self.stream.current.type == 'string':
buf.append(self.stream.current.value)
next(self.stream)
node = nodes.Const(''.join(buf), lineno=lineno)
elif token.type in ('integer', 'float'):
next(self.stream)
node = nodes.Const(token.value, lineno=token.lineno)
elif token.type == 'lparen':
next(self.stream)
node = self.parse_tuple(explicit_parentheses=True)
self.stream.expect('rparen')
elif token.type == 'lbracket':
node = self.parse_list()
elif token.type == 'lbrace':
node = self.parse_dict()
else:
self.fail("unexpected '%s'" % describe_token(token), token.lineno)
return node
def parse_tuple(self,
simplified=False,
with_condexpr=True,
extra_end_rules=None,
explicit_parentheses=False):
"""Works like `parse_expression` but if multiple expressions are
delimited by a comma a :class:`~ambari_jinja2.nodes.Tuple` node is created.
This method could also return a regular expression instead of a tuple
if no commas where found.
The default parsing mode is a full tuple. If `simplified` is `True`
only names and literals are parsed. The `no_condexpr` parameter is
forwarded to :meth:`parse_expression`.
Because tuples do not require delimiters and may end in a bogus comma
an extra hint is needed that marks the end of a tuple. For example
for loops support tuples between `for` and `in`. In that case the
`extra_end_rules` is set to ``['name:in']``.
`explicit_parentheses` is true if the parsing was triggered by an
expression in parentheses. This is used to figure out if an empty
tuple is a valid expression or not.
"""
lineno = self.stream.current.lineno
if simplified:
parse = self.parse_primary
elif with_condexpr:
parse = self.parse_expression
else:
parse = lambda: self.parse_expression(with_condexpr=False)
args = []
is_tuple = False
while 1:
if args:
self.stream.expect('comma')
if self.is_tuple_end(extra_end_rules):
break
args.append(parse())
if self.stream.current.type == 'comma':
is_tuple = True
else:
break
lineno = self.stream.current.lineno
if not is_tuple:
if args:
return args[0]
# if we don't have explicit parentheses, an empty tuple is
# not a valid expression. This would mean nothing (literally
# nothing) in the spot of an expression would be an empty
# tuple.
if not explicit_parentheses:
self.fail('Expected an expression, got \'%s\'' %
describe_token(self.stream.current))
return nodes.Tuple(args, 'load', lineno=lineno)
def parse_tuple(self, simplified=False, with_condexpr=True,
extra_end_rules=None, explicit_parentheses=False):
"""Works like `parse_expression` but if multiple expressions are
delimited by a comma a :class:`~ambari_jinja2.nodes.Tuple` node is created.
This method could also return a regular expression instead of a tuple
if no commas where found.
The default parsing mode is a full tuple. If `simplified` is `True`
only names and literals are parsed. The `no_condexpr` parameter is
forwarded to :meth:`parse_expression`.
Because tuples do not require delimiters and may end in a bogus comma
an extra hint is needed that marks the end of a tuple. For example
for loops support tuples between `for` and `in`. In that case the
`extra_end_rules` is set to ``['name:in']``.
`explicit_parentheses` is true if the parsing was triggered by an
expression in parentheses. This is used to figure out if an empty
tuple is a valid expression or not.
"""
lineno = self.stream.current.lineno
if simplified:
parse = self.parse_primary
elif with_condexpr:
parse = self.parse_expression
else:
parse = lambda: self.parse_expression(with_condexpr=False)
args = []
is_tuple = False
while 1:
if args:
self.stream.expect('comma')
if self.is_tuple_end(extra_end_rules):
break
args.append(parse())
if self.stream.current.type == 'comma':
is_tuple = True
else:
break
lineno = self.stream.current.lineno
if not is_tuple:
if args:
return args[0]
# if we don't have explicit parentheses, an empty tuple is
# not a valid expression. This would mean nothing (literally
# nothing) in the spot of an expression would be an empty
# tuple.
if not explicit_parentheses:
self.fail('Expected an expression, got \'%s\'' %
describe_token(self.stream.current))
return nodes.Tuple(args, 'load', lineno=lineno)
