Welcome to Python Railway-Oriented Programming documentation!¶
pyrop¶
Overview¶
Imperative-style railway-oriented programming in Python, including fully-typed errors. Supports sync and async functions and methods.
Getting Started¶
Install pyrop:
pip install pyrop
A simple example:
from pyrop import EitherMonad, Left, catch, monadic
catcher = catch[ValueError | TypeError]()
@catcher
def func_with_error() -> None:
raise ValueError("This is an error")
@catcher
def success_func() -> int:
return 1
@monadic
def func(do: EitherMonad[ValueError | TypeError]) -> int:
value = do << success_func()
print(f"Value is {value}")
do << func_with_error()
print("This will not execute")
return value
res = func()
assert isinstance(res, Left)
assert isinstance(res.value, ValueError)
try:
func().get()
except ValueError as e:
print(f"Caught error: {e}")
assert func().map_left(lambda e: "Error occurred") == Left("Error occurred")
assert func().get_or_else(1) == 1
Links¶
See the documentation here.
Development Status¶
This project is currently in early-stage development. There may be breaking changes often. While the major version is 0, minor version upgrades will often have breaking changes.
Developing¶
See the development guide for development details.