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JavaScript JavaScript and the DOM (Retiring) Making Changes to the DOM Styling Elements

Posted by Hanzhang Luo
Hanzhang Luo
6,517 Points

Why does Guil use two = sign instead of 3

Why?

1 Answer

Jason Hill
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Jason Hill
Full Stack JavaScript Techdegree Student 11,399 Points
Jason Hill
.a{fill-rule:evenodd;}techdegree
Jason Hill
Full Stack JavaScript Techdegree Student 11,399 Points

So the difference is the == is 'loose' equality, and the ===is STRICT. The === will check that the type and the value compared are the same, while ==will try to convert two types then compare.
ex: true === true is true, 77 === 77 is true however 77 === '77' is false, because '77' is a string. While 77 == '77'will be true, even though one is a string as well as false == 0, will be true. It is called type coercion. Checkout MDN for more info! If this helps you can select it as best answer.

Andrew Hickman
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Andrew Hickman
Full Stack JavaScript Techdegree Student 2,281 Points
Andrew Hickman
.a{fill-rule:evenodd;}techdegree
Andrew Hickman
Full Stack JavaScript Techdegree Student 2,281 Points

Yes. A good rule of thumb is to ALWAYS use ===, just like it is always good to write a "use strict" statement at the top of your files. It basically forces you to write good code.