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.



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switch
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