防抖、节流、call、bind、apply、new、柯里化实现

function throttle(fn, threshhold) {    var last, timerId;    threshhold || (threshhold = 250);
    return function() {      var now = Date.now();      if(last && now - last < threshhold) {        clearTimeout(timerId);        timerId = setTimeout(() => {          fn.apply(this, arguments);        }, threshhold)      } else {        last = now;        fn.apply(this, arguments);      }    }  }

function debounce(fn, interval) {    var timerId = null;
    return function() {      clearTimeout(timerId);      timerId = setTimeout(() => {        fn.apply(this, arguments)      }, interval)    }  }

Function.prototype.call = function(cxt, ...args) {    ctx || (ctx = window);    ctx.fn = this;
    let args = [];    let r = eval(`ctx.fn(${args})`);    delete ctx.fn;
    return r;  }

Funtion.prototype.apply = function(ctx, args) {    ctx || (ctx = window);    ctx.fn = this;
    let r = eval(`ctx.fn(${args})`)    delete ctx.fn;
    return r;  }

Funtion.prototype.bind = function(obj) {    if(type of this !== 'function') {      return;    }
    var _self = this;    var args = [].slice.call(arguments, 1);    return function() {      return _self.apply(obj, args.concat([].slice.call(arguments)))    }  }

function newOps (ctor) {      if(typeof ctor !== 'function') {        throw new Error('the first param must be a function');      }
      const new0bj = Object.create(ctor.prototype);      const args = [].slice.call(arguments, 1);
      const ctorReturnResult = ctor.apply(newObj, args);
      if((typeof ctorReturnResult === 'object' && typeof ctorReturnResult !== null) || typeof ctorReturnResult === 'function') {        return ctorReturnResult;      }      return newObj;    }

function currying(fn) {  const argArr = [];  let closure = function(...args) {    if(args.length > 0) {      argArr = [...argArr, ...args];      return closure;    }    return fn(...argArr);  }  return closure;}

function Dog(color) {
  Animal.apply(this, arguments);
  this.name = 'dog';
}
/* 注意下面两行 */
Dog.prototype = Object.create(Animal.prototype);
Dog.prototype.constructor = Dog;

function fib(n) {  if(n === 0 || n === 1) return n;  return fib(n - 2) + fib(n - 1);}

let fib = (function() {  let memory = []  return function(n) {      if(memory[n] !== undefined) {        return memory[n]    }    return memory[n] = (n === 0 || n === 1) ? n : fibonacci(n-1) + fibonacci(n-2)  }})()