label

The labeled statement can be used with break or continue statements. It is prefixing a statement with an identifier which you can refer to.

Syntax

label :
   statement

label

Any JavaScript identifier that is not a reserved word.

statement

Statements. break can be used with any labeled statement, and continue can be used with looping labeled statements.

Description

You can use a label to identify a loop, and then use the break or continue statements to indicate whether a program should interrupt the loop or continue its execution.

Note that JavaScript has NO goto statement, you can only use labels with break or continue.

Examples

Using a labeled continue with for loops

var i, j;

loop1:
for (i = 0; i < 3; i++) {      //The first for statement is labeled "loop1"
   loop2:
   for (j = 0; j < 3; j++) {   //The second for statement is labeled "loop2"
      if (i === 1 && j === 1) {
         continue loop1;
      }
      console.log("i = " + i + ", j = " + j);
   }
}

// Output is:
//   "i = 0, j = 0"
//   "i = 0, j = 1"
//   "i = 0, j = 2"
//   "i = 1, j = 0"
//   "i = 2, j = 0"
//   "i = 2, j = 1"
//   "i = 2, j = 2"
// Notice how it skips both "i = 1, j = 1" and "i = 1, j = 2"

Using a labeled continue statement

Given an array of items and an array of tests, this example counts the number of items that passes all the tests.

var itemsPassed = 0;
var i, j;

top:
for (i = 0; i < items.length; i++){
  for (j = 0; j < tests.length; j++) {
    if (!tests[j].pass(items[i])) {
      continue top;
    }
  }

  itemsPassed++;
}

Using a labeled break with for loops

var i, j;

loop1:
for (i = 0; i < 3; i++) {      //The first for statement is labeled "loop1"
   loop2:
   for (j = 0; j < 3; j++) {   //The second for statement is labeled "loop2"
      if (i === 1 && j === 1) {
         break loop1;
      }
      console.log("i = " + i + ", j = " + j);
   }
}

// Output is:
//   "i = 0, j = 0"
//   "i = 0, j = 1"
//   "i = 0, j = 2"
//   "i = 1, j = 0"
// Notice the difference with the previous continue example

Using a labeled break statement

Given an array of items and an array of tests, this example determines whether all items pass all tests.

var allPass = true;
var i, j;

top:
for (i = 0; items.length; i++)
  for (j = 0; j < tests.length; i++)
    if (!tests[j].pass(items[i])){
      allPass = false;
      break top;
    }

Specifications

Browser compatibility

See also

• break
• continue