Javascript-Channel.com

JavaScript Lint is an iteresting tool. You can check all your JavaScript source code for common mistakes without actually running the script or opening the web page.

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.
• Comments within comments.
• Ambiguity whether two adjacent lines are part of the same statement.
• Statements that don’t do anything.

JavaScript Lint also looks for the following less common mistakes:

• Regular expressions that are not preceded by a left parenthesis, assignment, colon, or comma.
• Statements that are separated by commas instead of semicolons.
• Use of increment (++) and decrement (–) except for simple statements such as “i++;” or “–i;”.
• Use of the void type.
• Successive plus (e.g. x+++y) or minus (e.g. x—y) signs.
• Use of labeled for and while loops.
• if, for, while, etc. without curly braces. (This check is disabled by default.)