curry.js

import _curry1 from './internal/_curry1';
import curryN from './curryN';


/**
 * Returns a curried equivalent of the provided function. The curried function
 * has two unusual capabilities. First, its arguments needn't be provided one
 * at a time. If `f` is a ternary function and `g` is `R.curry(f)`, the
 * following are equivalent:
 *
 *   - `g(1)(2)(3)`
 *   - `g(1)(2, 3)`
 *   - `g(1, 2)(3)`
 *   - `g(1, 2, 3)`
 *
 * Secondly, the special placeholder value [`R.__`](#__) may be used to specify
 * "gaps", allowing partial application of any combination of arguments,
 * regardless of their positions. If `g` is as above and `_` is [`R.__`](#__),
 * the following are equivalent:
 *
 *   - `g(1, 2, 3)`
 *   - `g(_, 2, 3)(1)`
 *   - `g(_, _, 3)(1)(2)`
 *   - `g(_, _, 3)(1, 2)`
 *   - `g(_, 2)(1)(3)`
 *   - `g(_, 2)(1, 3)`
 *   - `g(_, 2)(_, 3)(1)`
 *
 * @func
 * @memberOf R
 * @since v0.1.0
 * @category Function
 * @sig (* -> a) -> (* -> a)
 * @param {Function} fn The function to curry.
 * @return {Function} A new, curried function.
 * @see R.curryN, R.partial
 * @example
 *
 *      const addFourNumbers = (a, b, c, d) => a + b + c + d;
 *
 *      const curriedAddFourNumbers = R.curry(addFourNumbers);
 *      const f = curriedAddFourNumbers(1, 2);
 *      const g = f(3);
 *      g(4); //=> 10
 */
var curry = _curry1(function curry(fn) {
  return curryN(fn.length, fn);
});
export default curry;