JavaScript: The Good Parts

var Statement

JavaScript allows var definitions to occur anywhere within a function. JSLint is stricter.

JSLint expects that:

• A var will be declared only once, and that it will be declared before it is used.

• A function will be declared before it is used.

• Parameters will not also be declared as vars.

JSLint does not expect:

• The arguments array to be declared as a var.

• That a variable will be declared in a block. This is because JavaScript blocks do not have block scope. This can have unexpected consequences, so define all variables at the top of the function body.