Are parentheses ignored when assigning JSX to a variable

user_11746296 0
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I'm learning about the javascript basics. The two lines of code seem equivalent and I'm wondering if the parser simply ignores the parentheses in the second case:

var a = 5 + 5;

var b = (5 + 5);

EDIT: I realize the context of the question might of help after going through the comments, which are helpful. I was trying to assign some JSX to a variable and noticed that the parentheses seem optional:

var a = 
  <div>
    <SomeComponent />
  </div>;

var b = (
  <div>
    <SomeComponent />
  </div>
);

In the case of a return statement, I understand that parentheses are needed due to automatic semicolon injection. But in case of a simple assignment do the parentheses still matter?

EDIT 2: Thanks for the comments and answer that help me narrow down and articulate my question. I think what I really meant to ask is, does JSX parser (e.g. Babel) ignore the parentheses in such a case? Since both will be transpiled into:

var a = React.createElement(
  "div",
  null, 
  React.createElement(
    SomeComponent, 
    null
  )
)
jsx babeljs reactjs variable-assignment javascript
1 Answers

They're not ignored, but simple mathematics tells you that:

5 + 5 == (5 + 5)

If you had a different set of values, it would change - e.g.:

var a = (5 * 5) + 5 * 5;
var b = 5 * (5 + 5) * 5;
var c = 5 * 5 + (5 * 5);
var d = (5 * 5 + 5) * 5;
var e = 5 * (5 + 5 * 5);
var f = (5 * 5 + 5 * 5);

console.log(a); // 50
console.log(b); // 250
console.log(c); // 50
console.log(d); // 150
console.log(e); // 150
console.log(f); // 50

It depends on the Order of Operations (aka BODMAS/BIDMAS/BEDMAS etc.)

user_102217650
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