def parse_include(self):
node = nodes.Include(lineno=next(self.stream).lineno)
node.template = self.parse_expression()
if self.stream.current.test('name:ignore') and \
self.stream.look().test('name:missing'):
node.ignore_missing = True
self.stream.skip(2)
else:
node.ignore_missing = False
return self.parse_import_context(node, True)
python类next()的实例源码
def parse_import(self):
node = nodes.Import(lineno=next(self.stream).lineno)
node.template = self.parse_expression()
self.stream.expect('name:as')
node.target = self.parse_assign_target(name_only=True).name
return self.parse_import_context(node, False)
def parse_call_block(self):
node = nodes.CallBlock(lineno=next(self.stream).lineno)
if self.stream.current.type == 'lparen':
self.parse_signature(node)
else:
node.args = []
node.defaults = []
node.call = self.parse_expression()
if not isinstance(node.call, nodes.Call):
self.fail('expected call', node.lineno)
node.body = self.parse_statements(('name:endcall',), drop_needle=True)
return node
def parse_filter_block(self):
node = nodes.FilterBlock(lineno=next(self.stream).lineno)
node.filter = self.parse_filter(None, start_inline=True)
node.body = self.parse_statements(('name:endfilter',),
drop_needle=True)
return node
def parse_macro(self):
node = nodes.Macro(lineno=next(self.stream).lineno)
node.name = self.parse_assign_target(name_only=True).name
self.parse_signature(node)
node.body = self.parse_statements(('name:endmacro',),
drop_needle=True)
return node
def parse_print(self):
node = nodes.Output(lineno=next(self.stream).lineno)
node.nodes = []
while self.stream.current.type != 'block_end':
if node.nodes:
self.stream.expect('comma')
node.nodes.append(self.parse_expression())
return node
def parse_not(self):
if self.stream.current.test('name:not'):
lineno = next(self.stream).lineno
return nodes.Not(self.parse_not(), lineno=lineno)
return self.parse_compare()
def parse_add(self):
lineno = self.stream.current.lineno
left = self.parse_sub()
while self.stream.current.type == 'add':
next(self.stream)
right = self.parse_sub()
left = nodes.Add(left, right, lineno=lineno)
lineno = self.stream.current.lineno
return left
def parse_sub(self):
lineno = self.stream.current.lineno
left = self.parse_concat()
while self.stream.current.type == 'sub':
next(self.stream)
right = self.parse_concat()
left = nodes.Sub(left, right, lineno=lineno)
lineno = self.stream.current.lineno
return left
def parse_concat(self):
lineno = self.stream.current.lineno
args = [self.parse_mul()]
while self.stream.current.type == 'tilde':
next(self.stream)
args.append(self.parse_mul())
if len(args) == 1:
return args[0]
return nodes.Concat(args, lineno=lineno)
def parse_mul(self):
lineno = self.stream.current.lineno
left = self.parse_div()
while self.stream.current.type == 'mul':
next(self.stream)
right = self.parse_div()
left = nodes.Mul(left, right, lineno=lineno)
lineno = self.stream.current.lineno
return left
def parse_div(self):
lineno = self.stream.current.lineno
left = self.parse_floordiv()
while self.stream.current.type == 'div':
next(self.stream)
right = self.parse_floordiv()
left = nodes.Div(left, right, lineno=lineno)
lineno = self.stream.current.lineno
return left
def parse_mod(self):
lineno = self.stream.current.lineno
left = self.parse_pow()
while self.stream.current.type == 'mod':
next(self.stream)
right = self.parse_pow()
left = nodes.Mod(left, right, lineno=lineno)
lineno = self.stream.current.lineno
return left
def parse_pow(self):
lineno = self.stream.current.lineno
left = self.parse_unary()
while self.stream.current.type == 'pow':
next(self.stream)
right = self.parse_unary()
left = nodes.Pow(left, right, lineno=lineno)
lineno = self.stream.current.lineno
return left
def parse_unary(self, with_filter=True):
token_type = self.stream.current.type
lineno = self.stream.current.lineno
if token_type == 'sub':
next(self.stream)
node = nodes.Neg(self.parse_unary(False), lineno=lineno)
elif token_type == 'add':
next(self.stream)
node = nodes.Pos(self.parse_unary(False), lineno=lineno)
else:
node = self.parse_primary()
node = self.parse_postfix(node)
if with_filter:
node = self.parse_filter_expr(node)
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_test(self, node):
token = next(self.stream)
if self.stream.current.test('name:not'):
next(self.stream)
negated = True
else:
negated = False
name = self.stream.expect('name').value
while self.stream.current.type == 'dot':
next(self.stream)
name += '.' + self.stream.expect('name').value
dyn_args = dyn_kwargs = None
kwargs = []
if self.stream.current.type == 'lparen':
args, kwargs, dyn_args, dyn_kwargs = self.parse_call(None)
elif self.stream.current.type in ('name', 'string', 'integer',
'float', 'lparen', 'lbracket',
'lbrace') and not \
self.stream.current.test_any('name:else', 'name:or',
'name:and'):
if self.stream.current.test('name:is'):
self.fail('You cannot chain multiple tests with is')
args = [self.parse_expression()]
else:
args = []
node = nodes.Test(node, name, args, kwargs, dyn_args,
dyn_kwargs, lineno=token.lineno)
if negated:
node = nodes.Not(node, lineno=token.lineno)
return node
def _parse_block(self, parser, allow_pluralize):
"""Parse until the next block tag with a given name."""
referenced = []
buf = []
while 1:
if parser.stream.current.type == 'data':
buf.append(parser.stream.current.value.replace('%', '%%'))
next(parser.stream)
elif parser.stream.current.type == 'variable_begin':
next(parser.stream)
name = parser.stream.expect('name').value
referenced.append(name)
buf.append('%%(%s)s' % name)
parser.stream.expect('variable_end')
elif parser.stream.current.type == 'block_begin':
next(parser.stream)
if parser.stream.current.test('name:endtrans'):
break
elif parser.stream.current.test('name:pluralize'):
if allow_pluralize:
break
parser.fail('a translatable section can have only one '
'pluralize section')
parser.fail('control structures in translatable sections are '
'not allowed')
elif parser.stream.eos:
parser.fail('unclosed translation block')
else:
assert False, 'internal parser error'
return referenced, concat(buf)
def parse(self, parser):
token = next(parser.stream)
if token.value == 'break':
return nodes.Break(lineno=token.lineno)
return nodes.Continue(lineno=token.lineno)
def parse(self, parser):
node = nodes.Scope(lineno=next(parser.stream).lineno)
assignments = []
while parser.stream.current.type != 'block_end':
lineno = parser.stream.current.lineno
if assignments:
parser.stream.expect('comma')
target = parser.parse_assign_target()
parser.stream.expect('assign')
expr = parser.parse_expression()
assignments.append(nodes.Assign(target, expr, lineno=lineno))
node.body = assignments + \
list(parser.parse_statements(('name:endwith',),
drop_needle=True))
return node
