IceSpringRealOptional

Real Optional type in python, not @Nullable annotation.

Official sites

• Home: https://baijifeilong.github.io/2022/01/09/ice-spring-real-optional/index.html
• Github: https://github.com/baijifeilong/IceSpringRealOptional
• PyPI: https://pypi.org/project/IceSpringRealOptional

Features

• All Java 8 style Optional API support
• All Generic Type annotation support

Install

• PyPI: pip install IceSpringRealOptional

Usage

from IceSpringRealOptional.maybe import Maybe

maybe = Maybe.ofNullable("CommonSense")
print("{}: isPresent={}".format(maybe, maybe.isPresent()))
print("{}: value={}".format(maybe, maybe.get()))
maybe.ifPresent(lambda x: print(f"{x} exist"))
print("{}'s length: {}".format(maybe, maybe.map(len)))

empty = Maybe.empty()
print(empty.orElse("{} is empty".format(empty)))
print(empty.orElseGet(lambda: "{} is empty again".format(empty)))

try:
    Maybe.empty().orElseThrow(lambda: RuntimeError("Unlucky"))
except RuntimeError as e:
    print("Runtime error caught: {}".format(e))

Example Output

<Maybe:CommonSense>: isPresent=True
<Maybe:CommonSense>: value=CommonSense
CommonSense exist
<Maybe:CommonSense>'s length: <Maybe:11>
<Maybe:None> is empty
<Maybe:None> is empty again
Runtime error caught: Unlucky

License

MIT