JavaScript

JavaScript and IE11

Note to Internet Explorer 11 JavaScript Programmers.

Internet Explorer 11 implemented a version of JavaScript called ES5 – This was considered the state of the art in 2009. However in 2015 ES6 (aka ES 2015) was released, and it had quite a lot of enhancements, then in 2017 ES 2016 was released, then in 2018 ES 2018 was released, in 2019 ES 2019 was released.

In short, JavaScript has evolved quite a lot to the point where a lot of today’s JavaScript developers write code like this:

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getEmployees() {
    this.service
        .getEmployees()
        .subscribe(
          result => {
              if(result.wasSuccessful === false){
                alert('oops');
              }else{
                this.employees = result.model;
              }
              console.log(result);
            },
          error => console.error(error)
        );
}

If you study the code carefully, you see

  • output of a function is being fed into another function …getEmployees().subscribe
  • are whole statements, and even functions in place of parameters of functions.
  • => { notation – which I think means for each object coming in , call that object ‘result’ and execute the following code on it. (the stuff after =>