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JavaScript JavaScript and the DOM (Retiring) Traversing the DOM Using previousElementSibling and insertBefore

Posted by Justin Wu
Justin Wu
7,300 Points

why not && in the existing if?

I added another condition in the 'if' that checks if the list item is the first child of the parent ul before moving it up. If the list item is the first child, don't do anything.

I noticed in the video another 'if' is written that simply checks for the existence of a previous list item before moving the list item up.

Advantages/disadvantages of the two methods? Or is it simply preference?

2 Answers

Steven Parker
Steven Parker
231,271 Points
Steven Parker
Steven Parker
231,271 Points

:point_right: Expanding the if condition is preferable if the expressions are clear.

In the video, there were 3 lines of code between the first and second if. But assuming your condensation is not to convoluted, that would be a good optimization.

Michael Braga
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PLUS
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Michael Braga
Full Stack JavaScript Techdegree Graduate 24,174 Points
Michael Braga
.a{fill-rule:evenodd;}techdegree seal-36
Michael Braga
Full Stack JavaScript Techdegree Graduate 24,174 Points

Nested if statements become hard to read and just looks ugly if it becomes too much. Adding multiple logical operators can add complexity to your code especially if there are multiple operators. I personally try to find a balance of the two or try to minimize conditions as much as I can.