JavaScript: The Definitive Guide, 6th Edition

Summary of JavaScript Statements

This chapter introduced each of the JavaScript language’s statements. Table 5-1 summarizes them, listing the syntax and purpose of each.

Table 5-1. JavaScript statement syntax

Statement	Syntax	Purpose
break	break [label];	Exit from the innermost loop or switch or from named enclosing statement
case	case expression:	Label a statement within a switch
continue	continue [label];	Begin next iteration of the innermost loop or the named loop
debugger	debugger;	Debugger breakpoint
default	default:	Label the default statement within a switch
do/while	do statement while (expression);	An alternative to the while loop
empty	;	Do nothing
for	for(init; test; incr) statement	An easy-to-use loop
for/in	for (var in object) statement	Enumerate the properties of object
function	function name([param[,...]]) { body }	Declare a function named name
if/else	if (expr) statement1 [else statement2]	Execute statement1 or statement2
label	label: statement	Give statement the name label
return	return [expression];	Return a value from a function
switch	switch (expression) { statements }	Multiway branch to case or default: labels
throw	throw expression;	Throw an exception
try	try { statements } [catch { handler statements }] [finally { cleanup statements }]	Handle exceptions
use strict	"use strict";	Apply strict mode restrictions to script or function
var	var name [ = expr] [ ,... ];	Declare and initialize one or more variables
while	while (expression) statement	A basic loop construct
with	with (