apache_beam.typehints.trivial_inference module

Trivial type inference for simple functions.

For internal use only; no backwards-compatibility guarantees.

exception apache_beam.typehints.trivial_inference.TypeInferenceError[source]

Bases: ValueError

Error to raise when type inference failed.

apache_beam.typehints.trivial_inference.instance_to_type(o)[source]: Given a Python object o, return the corresponding type hint.

apache_beam.typehints.trivial_inference.union_list(xs, ys)[source]

class apache_beam.typehints.trivial_inference.Const(value)[source]

Bases: object

static unwrap(x)[source]

static unwrap_all(xs)[source]

class apache_beam.typehints.trivial_inference.FrameState(f, local_vars=None, stack=(), kw_names=None)[source]

Bases: object

Stores the state of the frame at a particular point of execution.

copy()[source]

const_type(i)[source]

get_closure(i)[source]

closure_type(i)[source]: Returns a TypeConstraint or Const.

get_global(i)[source]

get_name(i)[source]

apache_beam.typehints.trivial_inference.union(a, b)[source]: Returns the union of two types or Const values.

apache_beam.typehints.trivial_inference.finalize_hints(type_hint)[source]: Sets type hint for empty data structures to Any.

apache_beam.typehints.trivial_inference.element_type(hint)[source]: Returns the element type of a composite type.

apache_beam.typehints.trivial_inference.key_value_types(kv_type)[source]: Returns the key and value type of a KV type.

class apache_beam.typehints.trivial_inference.BoundMethod(func, type)[source]

Bases: object

Used to create a bound method when we only know the type of the instance.

Instantiates a bound method object.

Parameters:

func (types.FunctionType) – The method’s underlying function
type (type) – The class of the method.

apache_beam.typehints.trivial_inference.hashable(c)[source]

apache_beam.typehints.trivial_inference.infer_return_type(c, input_types, debug=False, depth=5)[source]

Analyses a callable to deduce its return type.

Parameters:

c – A Python callable to infer the return type of.
input_types – A sequence of inputs corresponding to the input types.
debug – Whether to print verbose debugging information.
depth – Maximum inspection depth during type inference.

Returns:

A TypeConstraint that that the return value of this function will (likely) satisfy given the specified inputs.

apache_beam.typehints.trivial_inference.infer_return_type_func(f, input_types, debug=False, depth=0)[source]

Analyses a function to deduce its return type.

Parameters:

f – A Python function object to infer the return type of.
input_types – A sequence of inputs corresponding to the input types.
debug – Whether to print verbose debugging information.
depth – Maximum inspection depth during type inference.

Returns:

A TypeConstraint that that the return value of this function will (likely) satisfy given the specified inputs.

Raises:

TypeInferenceError – if no type can be inferred.

apache_beam.typehints.trivial_inference.resolve_dataclass_field_type(x)[source]

Resolve a type to Beam typehint under global pipeline option context.

Since Beam 2.75.0, typehints of dataclass fields are honored during type inferences. However, in case of breakage (possible scenarios include incorrect typehints; non-deterministic or nullable types disallowed by consumer transform but check disabled by Any; tests rely on Any), –exclude_infer_dataclass_field_type option to instruct falling back to Any. Fields of builtin primitives are always respected.