either.js•1.29 kB
var _curry2 = require('./internal/_curry2');
var _isFunction = require('./internal/_isFunction');
var lift = require('./lift');
var or = require('./or');
/**
* A function wrapping calls to the two functions in an `||` operation,
* returning the result of the first function if it is truth-y and the result
* of the second function otherwise. Note that this is short-circuited,
* meaning that the second function will not be invoked if the first returns a
* truth-y value.
*
* In addition to functions, `R.either` also accepts any fantasy-land compatible
* applicative functor.
*
* @func
* @memberOf R
* @since v0.12.0
* @category Logic
* @sig (*... -> Boolean) -> (*... -> Boolean) -> (*... -> Boolean)
* @param {Function} f a predicate
* @param {Function} g another predicate
* @return {Function} a function that applies its arguments to `f` and `g` and `||`s their outputs together.
* @see R.or
* @example
*
* var gt10 = x => x > 10;
* var even = x => x % 2 === 0;
* var f = R.either(gt10, even);
* f(101); //=> true
* f(8); //=> true
*/
module.exports = _curry2(function either(f, g) {
return _isFunction(f) ?
function _either() {
return f.apply(this, arguments) || g.apply(this, arguments);
} :
lift(or)(f, g);
});