Section 6.10. Labels


6.10. Labels

The case and default: labels used with the switch statement are a special case of a more general label statement. Any statement may be labeled by preceding it with an identifier name and a colon:

 identifier: statement 

The identifier can be any legal JavaScript identifier that is not a reserved word. Label names are distinct from variable and function names, so you do not need to worry about name collisions if you give a label the same name as a variable or function. Here is an example of a labeled while statement:

 parser:   while(token != null) {       // Code omitted here } 

By labeling a statement, you give it a name that you can use to refer to it elsewhere in your program. You can label any statement, although the only statements that are commonly labeled are loops: while, do/while, for, and for/in. By giving a loop a name, you can use break and continue to exit the loop or to exit a single iteration of the loop (see the following two sections).




JavaScript. The Definitive Guide
JavaScript: The Definitive Guide
ISBN: 0596101996
EAN: 2147483647
Year: 2004
Pages: 767

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