def field(type=PFIELD_NO_TYPE,
invariant=PFIELD_NO_INVARIANT,
initial=PFIELD_NO_INITIAL,
mandatory=False,
factory=PFIELD_NO_FACTORY,
serializer=PFIELD_NO_SERIALIZER):
"""
Field specification factory for :py:class:`PRecord`.
:param type: a type or iterable with types that are allowed for this field
:param invariant: a function specifying an invariant that must hold for the field
:param initial: value of field if not specified when instantiating the record
:param mandatory: boolean specifying if the field is mandatory or not
:param factory: function called when field is set.
:param serializer: function that returns a serialized version of the field
"""
types = set(type) if isinstance(
type, Iterable) and not isinstance(type, six.string_types) else set(
[type])
invariant_function = wrap_invariant(
invariant) if invariant != PFIELD_NO_INVARIANT and callable(
invariant) else invariant
field = _PField(type=types,
invariant=invariant_function,
initial=initial,
mandatory=mandatory,
factory=factory,
serializer=serializer)
_check_field_parameters(field)
return field
def field(type=PFIELD_NO_TYPE, invariant=PFIELD_NO_INVARIANT, initial=PFIELD_NO_INITIAL,
mandatory=False, factory=PFIELD_NO_FACTORY, serializer=PFIELD_NO_SERIALIZER):
"""
Field specification factory for :py:class:`PRecord`.
:param type: a type or iterable with types that are allowed for this field
:param invariant: a function specifying an invariant that must hold for the field
:param initial: value of field if not specified when instantiating the record
:param mandatory: boolean specifying if the field is mandatory or not
:param factory: function called when field is set.
:param serializer: function that returns a serialized version of the field
"""
# NB: We have to check this predicate separately from the predicates in
# `maybe_parse_user_type` et al. because this one is related to supporting
# the argspec for `field`, while those are related to supporting the valid
# ways to specify types.
# Multiple types must be passed in one of the following containers. Note
# that a type that is a subclass of one of these containers, like a
# `collections.namedtuple`, will work as expected, since we check
# `isinstance` and not `issubclass`.
if isinstance(type, (list, set, tuple)):
types = set(maybe_parse_many_user_types(type))
else:
types = set(maybe_parse_user_type(type))
invariant_function = wrap_invariant(invariant) if invariant != PFIELD_NO_INVARIANT and callable(invariant) else invariant
field = _PField(type=types, invariant=invariant_function, initial=initial,
mandatory=mandatory, factory=factory, serializer=serializer)
_check_field_parameters(field)
return field
def field(type=PFIELD_NO_TYPE, invariant=PFIELD_NO_INVARIANT, initial=PFIELD_NO_INITIAL,
mandatory=False, factory=PFIELD_NO_FACTORY, serializer=PFIELD_NO_SERIALIZER):
"""
Field specification factory for :py:class:`PRecord`.
:param type: a type or iterable with types that are allowed for this field
:param invariant: a function specifying an invariant that must hold for the field
:param initial: value of field if not specified when instantiating the record
:param mandatory: boolean specifying if the field is mandatory or not
:param factory: function called when field is set.
:param serializer: function that returns a serialized version of the field
"""
# NB: We have to check this predicate separately from the predicates in
# `maybe_parse_user_type` et al. because this one is related to supporting
# the argspec for `field`, while those are related to supporting the valid
# ways to specify types.
# Multiple types must be passed in one of the following containers. Note
# that a type that is a subclass of one of these containers, like a
# `collections.namedtuple`, will work as expected, since we check
# `isinstance` and not `issubclass`.
if isinstance(type, (list, set, tuple)):
types = set(maybe_parse_many_user_types(type))
else:
types = set(maybe_parse_user_type(type))
invariant_function = wrap_invariant(invariant) if invariant != PFIELD_NO_INVARIANT and callable(invariant) else invariant
field = _PField(type=types, invariant=invariant_function, initial=initial,
mandatory=mandatory, factory=factory, serializer=serializer)
_check_field_parameters(field)
return field
def field(
type=PFIELD_NO_TYPE,
invariant=PFIELD_NO_INVARIANT,
initial=PFIELD_NO_INITIAL,
mandatory=False,
factory=PFIELD_NO_FACTORY,
serializer=PFIELD_NO_SERIALIZER,
):
"""
Field specification factory for :py:class:`PRecord`.
:param type: a type or iterable with types that are allowed for this field
:param invariant: a function specifying an invariant that must hold for the field
:param initial: value of field if not specified when instantiating the record
:param mandatory: boolean specifying if the field is mandatory or not
:param factory: function called when field is set.
:param serializer: function that returns a serialized version of the field
"""
types = set(type) if isinstance(type, Iterable) and not isinstance(type, six.string_types) else set([type])
invariant_function = (
wrap_invariant(invariant) if invariant != PFIELD_NO_INVARIANT and callable(invariant) else invariant
)
field = _PField(
type=types,
invariant=invariant_function,
initial=initial,
mandatory=mandatory,
factory=factory,
serializer=serializer,
)
_check_field_parameters(field)
return field
