JavaScript Tutorials

Compound and Empty Statements

Just as the comma operator combines multiple expressions into a single expression, a statement block combines multiple statements into a single compound statement. A statement block is simply a sequence of statements enclosed within curly braces. Thus, the following lines act as a single statement and can be used anywhere that JavaScript expects a single statement:

x = Math.PI;
cx = Math.cos(x);
console.log("cos(π) = " + cx);

A compound statement allows you to use multiple statements where JavaScript syntax expects a single statement. The empty statement is the opposite: it allows you to include no statements where one is expected. The empty statement looks like this:


The JavaScript interpreter takes no action when it executes an empty statement. The empty statement is occasionally useful when you want to create a loop that has an empty body.

// Initialize an array a