thepabloaguilar

from returns.result import Failure, Result, Success

def is_even(number: int) -> Result[int, int]:
    if arg % 2 == 0:
        return Success(number)
    return Failure(number)

assert is_even(2) == Success(2)    
assert is_even(1) == Failure(1)

thepabloaguilar

import os

class Example:
    def __init__(self) -> None:
        if os.getenv('RETURNS_TRACE'):
            self._tracking = []

thepabloaguilar

from returns.result import Failure, Result
from returns.primitives.tracing import collect_traces

@collect_traces
def get_failure(argument: str) -> Result[str, str]:
    return Failure(argument)

failure = get_failure('example')

for trace_line in failure.trace:

thepabloaguilar

from returns.result import Result, Success, Failure

def example_function(arg: str) -> Result[int, str]:
    if arg.isnumeric():
        return Success(int(arg))
    return Failure('"{0}" is not a number'.format(arg))

def test_if_failure_is_created_at_example_function(returns):
    with returns.has_trace(Failure, example_function):
        Success('not a number').bind(example_function)

thepabloaguilar

package main

import (
	"fmt"
	"strconv"
)

func Map[T1, T2 any](s []T1, f func(T1) T2) []T2 {
	newSlice := make([]T2, 0)
	for _, item := range s {

thepabloaguilar

from abc import ABCMeta
from dataclasses import dataclass
from typing import (
    Any,
    ClassVar,
    Iterable,
    Protocol,
    Union,
    get_args,
    get_origin,

thepabloaguilar

• https://github.com/cognitect-labs/transducers-python/blob/master/tests/transducer_tests.py
• https://www.infoq.com/articles/saga-orchestration-outbox/
• https://github.com/clojure/clojure/blob/7529bc90a35eba940581311d7dfed21fec22b4f5/src/clj/clojure/core.clj#L6875
• https://github.com/cognitect-labs/transducers-python/blob/11ac3e5c78a5a9dd30719d3aba91bf333c249a94/transducers/transducers.py#L46
• https://medium.com/@olxc/referential-transparency-93352c2dd713