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JavaScript JavaScript Basics (Retired) Making Decisions with Conditional Statements Document Your Code With Comments

Posted by Francesco Nasso
Francesco Nasso
5,427 Points

// Comments vs /* */ Comments

I've seen a few JavaScript source files where the developer chose to use multiple single line comments (//) in place of a multiple line comment (/* */). Is using single line comments in this matter something that is frowned upon in production code? Additionally, from a does it make any difference to how a program interprets those comments?

1 Answer

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

A single line comment is in effect from where it starts ("//") to the end of the current line. A multi-line comment is in effect from where it starts ("/*") until it explicitly ends ("*/") no matter how many lines are involved.

I'm not aware of any general "best practice" rules that prefer one type over the other, but some organizations may provide their own code formatting specifications that they require developers to adhere to. In the absence of such rules I would expect it to be purely "programmer's choice".