switch statement
<programming> (Or case statement, multi-way branch) A construct found in
most high-level languages for selecting one of several possible blocks of code
or branch destinations depending on the value of an expression. An example in C
is
switch (foo(x, y))
{
case 1: printf("Hello\n"); /* fall through */
case 2: printf("Goodbye\n"); break;
case 3: printf("Fish\n"); break;
default: fprintf(stderr, "Odd foo value\n"); exit(1);
}
The break statements cause execution to continue after the whole switch
statemetnt. The lack of a break statement after the
first case means that execution will fall through
into the second case. Since this is a common
programming error you should add a comment if it is
intentional.
If none of the explicit cases matches the expression value then the (optional)
default case is taken.
A similar construct in some functional languages returns the value of one of
several expressions selected according to the value of the first expression. A
distant relation to the modern switch statement is Fortran's computed goto.
(1997-01-30)
Nearby terms:
switched virtual circuit « switched virtual
connection « switching hub « switch statement
» swizzle » SWL » SWT
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