Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
128 views
in Technique[技术] by (71.8m points)

javascript - Self-invoking function and "use strict" and default parameter

I need to dynamically warp some unknown code in an anonymous function and pass some parameters to it. e.g.

((win, a, b = a.info) => { 
  
  /* unknown code
  *  unknown code
  *  unknown code
  */
  
})(window, {info: {/*....*/}});

Above works fine but if the unknown code starts with "use strict" there will an error:

Uncaught SyntaxError: "use strict" not allowed in function with default parameter

Defining the variable inside the function would void "use strict", if present. e.g.

((win, a) => { const b = a.info;
  
  /* unknown code
  *  unknown code
  *  unknown code
  */
  
})(window, {info: {/*....*/}});

I can pass the parameter again but it is large and feels like a waste e.g.

((win, a, b) => { 

  /* unknown code
  *  unknown code
  *  unknown code
  */

})(window, {info: {/*....*/}}, {/*....*/});

Is there any other/better way to achieve the desired result? ??

Update: a possibility

It seems double wrapping in IIFE can solve the issue, although a bit ugly (but still much shorter than passing the variable twice).

((win, a, b = a.info) => { 
(() => {

  /* unknown code
  *  unknown code
  *  unknown code
  */
  
})();
})(window, {info: {/*....*/}});
question from:https://stackoverflow.com/questions/65932229/self-invoking-function-and-use-strict-and-default-parameter

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Reply

0 votes
by (71.8m points)
Waitting for answers

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
OGeek|极客中国-欢迎来到极客的世界,一个免费开放的程序员编程交流平台!开放,进步,分享!让技术改变生活,让极客改变未来! Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

1.4m articles

1.4m replys

5 comments

57.0k users

...