Labels
The
case
and
default:
labels used in conjunction with the switch
statement are a special case of a more general label statement. In
JavaScript 1.2, 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.
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