io.vavr.kotlin.Control.kt Maven / Gradle / Ivy

Go to download
/*  __    __  __  __    __  ___
 * \  \  /  /    \  \  /  /  __/
 *  \  \/  /  /\  \  \/  /  /
 *   \____/__/  \__\____/__/
 *
 * Copyright 2014-2017 Vavr, http://vavr.io
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package io.vavr.kotlin

import io.vavr.CheckedFunction0
import io.vavr.collection.Seq
import io.vavr.control.Either
import io.vavr.control.Option
import io.vavr.control.Option.none
import io.vavr.control.Option.some
import io.vavr.control.Try
import io.vavr.control.Validation

/**
 * Constructors and Kotlin collection extensions for Option, Try, Validation and Either
 *
 * @author Alex Zuzin (github.com/zvozin)
 */

/**
 * Creates an Option of a nullable.
 * @return None() for null, Some(this) for a present value
 */
fun  A?.option():
        Option = if (this == null) none() else some(this)

/**
 * @see Option.some
 */
fun  some(a: A):
        Option = Option.some(a)

/**
 * @see Option.none
 */
fun  none():
        Option = Option.none()

/**
 * Creates an Option predicated on a Boolean, using the supplied value.
 * @return Some(a) if this is true, None() otherwise
 */
fun  Boolean.option(a: A):
        Option = if (this) some(a) else none()

/**
 * Creates an Option predicated on a Boolean, using the supplier of value.
 * @return Some(a.invoke()) if this is true, None() otherwise
 */
fun  Boolean.option(a: () -> A):
        Option = if (this) some(a.invoke()) else none()

/**
 * @see Option.sequence
 */
fun  Iterable>.sequence():
        Option> = Option.sequence(this)


/**
 * @see Validation.invalid
 */
fun  invalid(a: A):
        Validation = Validation.invalid(a)

/**
 * @see Validation.valid
 */
fun  valid(b: B):
        Validation = Validation.valid(b)


/**
 * @see Either.left
 */
fun  left(a: A):
        Either = Either.left(a)

/**
 * @see Either.right
 */
fun  right(b: B):
        Either = Either.right(b)

/**
 * @see Validation.fromEither
 */
fun  Either.validation():
        Validation = Validation.fromEither(this)

/**
 * @see Validation.sequence
 */
fun  Iterable, T2>>.sequence():
        Validation, Seq> = Validation.sequence(this)

/**
 * @see Try.of
 */
fun  `try`(f: () -> A):
        Try = Try(f)

/**
 * @see Try.of
 */
fun  Try(f: () -> A):
        Try = Try.of(object : CheckedFunction0 {
            override fun apply(): A = f()
        })

/**
 * @see Try.success
 */
fun  success(a: A):
        Try = Try.success(a)

/**
 * @see Try.failure
 */
fun  failure(t: Exception):
        Try = Try.failure(t)

/**
 * @see Try.sequence
 */
fun  Iterable>.sequence():
        Try> = Try.sequence(this)