How to find Javascript syntax errors [closed]

Answer 1

The Eclipse IDE (with the JSEclipse plugin) identifies nearly all of our syntax problems.

I suggest one of the better editors is IntelliJ, but it's not free.

Answer 2

Chrome : Ctrl + Shift + J : this will bring up the JavaScript console. You can click the scripts tab to review page scripts.

FireFox : Install firebug and run it to get a similar console to the above stated chrome utilities.

IDE : You may wish to use netbeans or Eclipse which both offer syntax highlighting and code completion for JavaScript. These will indicate syntax errors at code time.

jslint/jshint : These tools offer code suggestions to improve your code quality and reduce the possibility of errors (logic) but will also break on syntax and other errors.

Answer 3

http://www.javascriptlint.com/

Here are some common mistakes that JavaScript Lint looks for:

• Missing semicolons at the end of a line.
• Curly braces without an if, for, while, etc.
• Code that is never run because of a return, throw, continue, or break.
• Case statements in a switch that do not have a break statement.
• Leading and trailing decimal points on a number.
• A leading zero that turns a number into octal (base 8).
• Comments within comments.
• Ambiguity whether two adjacent lines are part of the same statement.
• Statements that don't do anything.

Answer 4

You can use the Esprima JavaSript parser (the link is a online code editor ready to use).

I believe it's currently the best ready-to-use js parser in js, that's why I'm using it in my LIVEditor project (code editor for the html/css/js with real-time preview).

Answer 5

Douglas Crockford's Jslint: http://www.jslint.com/

But be warned, it will hurt your feelings ;-)

Answer 6

One idea would be to use Firebug console for interactively experimenting with you scripts and then moving only the tested parts into the your code.