Class Representer
Synopsis
class Representer(SafeRepresenter)
Description
No description yet.
Inheritance
Ancestors: SafeRepresenter
Methods
represent_complex | ||
represent_module | ||
represent_name | ||
represent_object | ||
represent_ordered_dict | ||
represent_tuple |
Source
Lines 272-390 in lib3/yaml/representer.py.
class Representer(SafeRepresenter):
def represent_complex(self, data):
if data.imag == 0.0:
data = '%r' % data.real
elif data.real == 0.0:
data = '%rj' % data.imag
elif data.imag > 0:
data = '%r+%rj' % (data.real, data.imag)
else:
data = '%r%rj' % (data.real, data.imag)
return self.represent_scalar('tag:yaml.org,2002:python/complex', data)
def represent_tuple(self, data):
return self.represent_sequence('tag:yaml.org,2002:python/tuple', data)
def represent_name(self, data):
name = '%s.%s' % (data.__module__, data.__name__)
return self.represent_scalar('tag:yaml.org,2002:python/name:'+name, '')
def represent_module(self, data):
return self.represent_scalar(
'tag:yaml.org,2002:python/module:'+data.__name__, '')
def represent_object(self, data):
# We use __reduce__ API to save the data. data.__reduce__ returns
# a tuple of length 2-5:
# (function, args, state, listitems, dictitems)
# For reconstructing, we calls function(*args), then set its state,
# listitems, and dictitems if they are not None.
# A special case is when function.__name__ == '__newobj__'. In this
# case we create the object with args[0].__new__(*args).
# Another special case is when __reduce__ returns a string - we don't
# support it.
# We produce a !!python/object, !!python/object/new or
# !!python/object/apply node.
cls = type(data)
if cls in copyreg.dispatch_table:
reduce = copyreg.dispatch_table[cls](data)
elif hasattr(data, '__reduce_ex__'):
reduce = data.__reduce_ex__(2)
elif hasattr(data, '__reduce__'):
reduce = data.__reduce__()
else:
raise RepresenterError("cannot represent an object", data)
reduce = (list(reduce)+[None]*5)[:5]
function, args, state, listitems, dictitems = reduce
args = list(args)
if state is None:
state = {}
if listitems is not None:
listitems = list(listitems)
if dictitems is not None:
dictitems = dict(dictitems)
if function.__name__ == '__newobj__':
function = args[0]
args = args[1:]
tag = 'tag:yaml.org,2002:python/object/new:'
newobj = True
else:
tag = 'tag:yaml.org,2002:python/object/apply:'
newobj = False
function_name = '%s.%s' % (function.__module__, function.__name__)
if not args and not listitems and not dictitems \
and isinstance(state, dict) and newobj:
return self.represent_mapping(
'tag:yaml.org,2002:python/object:'+function_name, state)
if not listitems and not dictitems \
and isinstance(state, dict) and not state:
return self.represent_sequence(tag+function_name, args)
value = {}
if args:
value['args'] = args
if state or not isinstance(state, dict):
value['state'] = state
if listitems:
value['listitems'] = listitems
if dictitems:
value['dictitems'] = dictitems
return self.represent_mapping(tag+function_name, value)
def represent_ordered_dict(self, data):
# Provide uniform representation across different Python versions.
data_type = type(data)
tag = 'tag:yaml.org,2002:python/object/apply:%s.%s' \
% (data_type.__module__, data_type.__name__)
items = [[key, value] for key, value in data.items()]
return self.represent_sequence(tag, [items])
Representer.add_representer(complex,
Representer.represent_complex)
Representer.add_representer(tuple,
Representer.represent_tuple)
Representer.add_representer(type,
Representer.represent_name)
Representer.add_representer(collections.OrderedDict,
Representer.represent_ordered_dict)
Representer.add_representer(types.FunctionType,
Representer.represent_name)
Representer.add_representer(types.BuiltinFunctionType,
Representer.represent_name)
Representer.add_representer(types.ModuleType,
Representer.represent_module)
Representer.add_multi_representer(object,
Representer.represent_object)