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break

label:
for ( var i = 0; i < limit; i++ ) {
    if ( condition ) {
        break label;
    }
}

switch ( expression ) {
    case 1:
        Statements1;
        break;
    default:
        DefaultStatements;
        break;
}

This keyword is used in for loops, do loops, while loops and switch statements. When a break statement is encountered in a loop, control is passed to the statement following the end of the inner-most loop that contains the break statement; unless the break statement is followed by the name of a label, in which case control passes to the statement governed by the label.

A break statement is usually placed at the end of each case in a switch statement to prevent the interpreter "falling through" to the next case. When the interpreter encounters a break statement, it passes control to the statement that follows the inner-most enclosing switch statement. If every case has a corresponding break, then at most one case's statements will be executed. If the break statement is followed by a label name (label) then when the break is encountered, control will pass to the statement marked with that label; this is useful, for example, for breaking out of deeply nested loops.

Example:

    red:
    for ( x = 0; x < object.width; x++ ) {
        for ( y = 0; y < object.height; y++ ) {
            if ( color[x][y] == 0xFF0000 ) {
                break red;
            }
        }
    }

See switch for another example. See also do, while, for and break.

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