JSLint - The JavaScript Code Quality Tool

JSLint is a JavaScript program that looks for problems in JavaScript programs. It is a code quality tool. JSLint takes a JavaScript source and scans it. If it finds a problem, it returns a message describing the problem and an approximate location within the source. The problem is not necessarily a syntax error, although it often is. JSLint looks at some style conventions as well as structural problems. It does not prove that your program is correct.

JavaScript is a young-for-its-age language. It was originally intended to do small tasks in webpages, tasks for which Java was too heavy and clumsy. But JavaScript is a very capable language, and it is now being used in larger projects. Many of the features that were intended to make the language easy to use are troublesome for larger projects. A lint for JavaScript is needed: JSLint, a JavaScript syntax checker and validator.

The source is available in location http://www.jslint.com/lint.html