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关于bind实现的一点建议

// bind返回函数,再在里面执行绑定在context的原函数 Function.prototype.myBind = function(context){ if (context === null || context === undefined) { throw Error(参数不能为${context}) } else { context = Object(context); } const symbolKey = Symbol('特殊键,用来存储原始this,即原始function'); context[symbolKey] = this; return function(...params){ context[symbolKey](...params); Reflect.deleteProperty(context, symbolKey); }; }

关于bind实现的一点建议

Function.prototype.myBind = function(context){
  if (context === null || context === undefined) {
    // this参数如果是null/undefined,就指向window,node环境为global
    try {
      context = window;
    } catch(e){
      context = global;
    }
  } else {
    context = Object(context);
  }
  const symbolKey = Symbol('特殊键,用来存储原始this,即原始function');
  context[symbolKey] = this;
  return function(...params){
    context[symbolKey](...params);
    Reflect.deleteProperty(context, symbolKey);
  };
}

这样可以摆脱对call的依赖,而且保持和myCall、myApply实现原理的一致性

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