ut2/lib/curry.js

一个现代 JavaScript 实用工具库。[点击查看在线文档]。

'use strict';

var native = require('./internals/native.js');
var isUndefined = require('./isUndefined.js');
var toInteger = require('./toInteger.js');

var PLACEHOLDER = {
    __ut2_curry_ph__: null
};
var curry = function (func, arity) {
    arity = isUndefined(arity) ? func.length : native.mathMax(toInteger(arity), 0);
    function wrap() {
        var args = native.arrayProtoSlice.call(arguments);
        var context = this;
        function inner() {
            var argsInner = native.arrayProtoSlice.call(arguments);
            for (var i = 0; i < args.length; i++) {
                args[i] = args[i] === PLACEHOLDER && argsInner.length > 0 ? argsInner.shift() : args[i];
            }
            args = args.concat(argsInner);
            var realArgsLength = args.filter(function (arg) { return arg !== PLACEHOLDER; }).length;
            if (realArgsLength >= arity) {
                return func.apply(context, args);
            }
            return inner;
        }
        return inner();
    }
    return wrap;
};
curry.placeholder = curry._ = PLACEHOLDER;

module.exports = curry;