Nested comment

When do I get this error?

The "Nested comment" error is thrown when JSLint encounters the character sequence /* inside a multiline comment. Here's an example:

/* This is a multiline comment.
   /* It's valid JavaScript,
   but JSLint doesn't like it */

Why do I get this error?

This error is raised to highlight a potentially dangerous piece of code. While it is valid to include the /* sequence in a multiline comment, it is not valid to include */. If you were to do so, everything following the first */ would be parsed as if it is not part of the comment. Here's an example (notice the syntax highlighting which demonstrates the error):

/* This is a multiline comment.
   /* It's valid JavaScript, */
   but JSLint doesn't like it */

You can resolve this issue by simply removing /* character sequences from multiline comments:

/* This is a multiline comment.
   It's valid JavaScript,
   but JSLint doesn't like it */

About the author

James Allardice

This article was written by James Allardice, JavaScript engineer at Mammal in London. Passionate about AngularJS, Node and writing clean and maintainable JavaScript and uses JSHint every day to help achieve this.