converge.js•1.61 kB
var _curry2 = require('./internal/_curry2');
var _map = require('./internal/_map');
var curryN = require('./curryN');
var max = require('./max');
var pluck = require('./pluck');
var reduce = require('./reduce');
/**
* Accepts a converging function and a list of branching functions and returns
* a new function. When invoked, this new function is applied to some
* arguments, each branching function is applied to those same arguments. The
* results of each branching function are passed as arguments to the converging
* function to produce the return value.
*
* @func
* @memberOf R
* @since v0.4.2
* @category Function
* @sig (x1 -> x2 -> ... -> z) -> [(a -> b -> ... -> x1), (a -> b -> ... -> x2), ...] -> (a -> b -> ... -> z)
* @param {Function} after A function. `after` will be invoked with the return values of
* `fn1` and `fn2` as its arguments.
* @param {Array} functions A list of functions.
* @return {Function} A new function.
* @example
*
* var add = (a, b) => a + b;
* var multiply = (a, b) => a * b;
* var subtract = (a, b) => a - b;
*
* //≅ multiply( add(1, 2), subtract(1, 2) );
* R.converge(multiply, [add, subtract])(1, 2); //=> -3
*
* var add3 = (a, b, c) => a + b + c;
* R.converge(add3, [multiply, add, subtract])(1, 2); //=> 4
*/
module.exports = _curry2(function converge(after, fns) {
return curryN(reduce(max, 0, pluck('length', fns)), function() {
var args = arguments;
var context = this;
return after.apply(context, _map(function(fn) {
return fn.apply(context, args);
}, fns));
});
});