Implementation of kotlin.Triple in JavaScript, TypeScript, and Python

//javascript
// Maybe type
const Maybe = (value) => ({
  map: (fn) => (value !== null && value !== undefined ? Maybe(fn(value)) : Maybe(null)),
  flatMap: (fn) => (value !== null && value !== undefined ? fn(value) : Maybe(null)),
  getOrElse: (defaultValue) => (value !== null && value !== undefined ? value : defaultValue),
});

// Either type
const Either = {
  Left: (value) => ({
    map: (fn) => Either.Left(value),
    flatMap: (fn) => Either.Left(value),
    getOrElse: (defaultValue) => defaultValue,
    isLeft: true,
    isRight: false,
  }),
  Right: (value) => ({
    map: (fn) => Either.Right(fn(value)),
    flatMap: (fn) => fn(value),
    getOrElse: (defaultValue) => value,
    isLeft: false,
    isRight: true,
  }),
};

// Triple class
class Triple {
  constructor(a, b, c) {
    this.a = a;
    this.b = b;
    this.c = c;
  }

  map(fn) {
    return new Triple(fn(this.a), fn(this.b), fn(this.c));
  }

  static of(a, b, c) {
    return new Triple(a, b, c);
  }

  // Example method using Maybe and Either
  divideBy(other) {
    return Maybe(this.b)
      .flatMap((numerator) =>
        Maybe(other)
          .flatMap((denominator) =>
            denominator !== 0
              ? Either.Right(numerator / denominator)
              : Either.Left('Division by zero')
          )
      )
      .getOrElse(Either.Left('Invalid input'));
  }
}

// Example usage
const triple = Triple.of(1, 2, 3);
const result = triple.map((x) => x * 2);
console.log(result); // Triple { a: 2, b: 4, c: 6 }

const divisionResult = triple.divideBy(2);
console.log(divisionResult); // Either.Right { value: 1 }

const invalidDivisionResult = triple.divideBy(0);
console.log(invalidDivisionResult); // Either.Left { value: 'Division by zero' }

//Typescript
// Maybe type
// noinspection JSAnnotator

type Maybe<T> = {
  map<U>(fn: (value: T) => U): Maybe<U>;
  flatMap<U>(fn: (value: T) => Maybe<U>): Maybe<U>;
  getOrElse(defaultValue: T): T;
};

const just = <T>(value: T): Maybe<T> => ({
  map: <U>(fn: (value: T) => U) => just(fn(value)),
  flatMap: <U>(fn: (value: T) => Maybe<U>) => fn(value),
  getOrElse: (_: T) => value,
});

const nothing = <T>(): Maybe<T> => ({
  map: <U>(_: (value: T) => U) => nothing<U>(),
  flatMap: <U>(_: (value: T) => Maybe<U>) => nothing<U>(),
  getOrElse: (defaultValue: T) => defaultValue,
});

// Either type
type Either<L, R> = {
  map<U>(fn: (value: R) => U): Either<L, U>;
  flatMap<U>(fn: (value: R) => Either<L, U>): Either<L, U>;
  getOrElse(defaultValue: R): R;
  isLeft: boolean;
  isRight: boolean;
};

const left = <L, R>(value: L): Either<L, R> => ({
  map: <U>(_: (value: R) => U) => left<L, U>(value),
  flatMap: <U>(_: (value: R) => Either<L, U>) => left<L, U>(value),
  getOrElse: (defaultValue: R) => defaultValue,
  isLeft: true,
  isRight: false,
});

const right = <L, R>(value: R): Either<L, R> => ({
  map: <U>(fn: (value: R) => U) => right<L, U>(fn(value)),
  flatMap: <U>(fn: (value: R) => Either<L, U>) => fn(value),
  getOrElse: (_: R) => value,
  isLeft: false,
  isRight: true,
});

// Triple class
class Triple<T> {
  constructor(public a: T, public b: T, public c: T) {}

  map<U>(fn: (value: T) => U): Triple<U> {
    return new Triple<U>(fn(this.a), fn(this.b), fn(this.c));
  }

  static of<T>(a: T, b: T, c: T): Triple<T> {
    return new Triple<T>(a, b, c);
  }

  // Example method using Maybe and Either
  divideBy(other: T): Either<string, number> {
    return just(this.b)
      .flatMap((numerator) =>
        just(other)
          .flatMap((denominator) =>
            denominator !== 0 ? right(numerator / denominator) : left('Division by zero')
          )
      )
      .getOrElse(left('Invalid input'));
  }
}

// Example usage
const triple = Triple.of(1, 2, 3);
const result = triple.map((x) => x * 2);
console.log(result); // Triple { a: 2, b: 4, c: 6 }

const divisionResult = triple.divideBy(2);
console.log(divisionResult); // Either.Right { value: 1 }

const invalidDivisionResult = triple.divideBy(0);
console.log(invalidDivisionResult); // Either.Left { value: 'Division by zero' }

pip install pydantic pymonad

from pymonad.either import Either, Left, Right
from pydantic import BaseModel, ValidationError, validator

# Définition de la classe Triple avec Pydantic
class Triple(BaseModel):
    a: int
    b: int
    c: int

    @validator('b')
    def validate_b(cls, b, values):
        if b == 0:
            raise ValueError('Division by zero is not allowed')
        return b

    # Méthode utilisant Either pour la gestion des erreurs
    def divide_by(self, other):
        def division(numerator, denominator):
            return Right(numerator / denominator)

        def handle_error(error):
            return Left(str(error))

        return Either(lambda: division(self.b, other)).or_else(handle_error)

# Exemple d'utilisation
try:
    triple = Triple(a=1, b=2, c=3)
    result = triple.divide_by(2)

    if result.is_right:
        print(f'Division result: {result.value}')
    else:
        print(f'Error: {result.value}')

except ValidationError as e:
    print(f'Validation Error: {e}')
except Exception as e:
    print(f'An unexpected error occurred: {e}')