fumus.utils.optional

Classes

Optional

Container object which may (or may not) contain a non-null value

Module Contents

class fumus.utils.optional.Optional(element)

Container object which may (or may not) contain a non-null value

__slots__ = ('_element',)

_element

classmethod empty()

Creates empty Optional

classmethod of(element)

Creates Optional describing given non-null value

classmethod of_nullable(element)

Returns an Optional describing the given value, if non-null, otherwise returns an empty Optional

get()

If a value is present, returns the value, otherwise raises an Exception

property is_present

Returns bool whether a value is present

property is_empty

Returns bool whether the Optional is empty

if_present(action)

Performs given action with the value if the Optional is not empty

if_present_or_else(action, empty_action)

Performs given action with the value if the Optional is not empty, otherwise calls fallback ‘empty_action’

or_else(value)

Returns the value if present, or a provided argument otherwise. Safe alternative to get() method

or_else_get(supplier)

Returns the value if present, or calls a ‘supplier’ function otherwise. Safe alternative to get() method

or_else_raise(supplier=None)

Returns the value if present, otherwise throws an exception produced by the exception supplying function (if such is provided by the user) or NoSuchElementError

map(mapper)

If a value is present, apply the provided mapping function to it, and if the result is non-null, return an Optional describing the result. Otherwise return an empty Optional. (NB: if the provided mapper returns an Optional, the result isn’t wrapped-up in an additional one)

filter(predicate)

If a value is present, and the value matches the given predicate, returns an Optional describing the value, otherwise returns an empty Optional

__repr__()

__eq__(other)

__hash__()