Innovenergy_trunk/frontend/node_modules/fp-ts/es6/Random.js

46 lines
1.4 KiB
JavaScript

/**
* @since 2.0.0
*/
import { map } from './IO';
import { pipe } from './function';
/**
* Returns a random number between 0 (inclusive) and 1 (exclusive). This is a direct wrapper around JavaScript's
* `Math.random()`.
*
* @since 2.0.0
*/
export var random = function () { return Math.random(); };
/**
* Takes a range specified by `low` (the first argument) and `high` (the second), and returns a random integer uniformly
* distributed in the closed interval `[low, high]`. It is unspecified what happens if `low > high`, or if either of
* `low` or `high` is not an integer.
*
* @since 2.0.0
*/
export function randomInt(low, high) {
return pipe(random, map(function (n) { return Math.floor((high - low + 1) * n + low); }));
}
/**
* Returns a random number between a minimum value (inclusive) and a maximum value (exclusive). It is unspecified what
* happens if `maximum < minimum`.
*
* @since 2.0.0
*/
export function randomRange(min, max) {
return pipe(random, map(function (n) { return (max - min) * n + min; }));
}
/**
* Returns a random boolean value with an equal chance of being `true` or `false`
*
* @since 2.0.0
*/
export var randomBool = /*#__PURE__*/ pipe(random, map(function (n) { return n < 0.5; }));
/**
* Returns a random element of a `ReadonlyNonEmptyArray`.
*
* @since 2.10.0
*/
export var randomElem = function (as) {
return pipe(randomInt(0, as.length - 1), map(function (i) { return as[i]; }));
};