switch/continue

[Christopher Benson-Manica]

Given the following snippet,

int i;

for( i=0 ; i < 10 ; i++ ) {
switch( i ) {
case 0: case 1:
continue; /* NB */
default:
/* do something */
}
}

The indicated continue statement will apply to the for loop, correct?

 

[Ben Pfaff]

for( i=0 ; i < 10 ; i++ ) {
switch( i ) {
case 0: case 1:
continue; /* NB */
default:
/* do something */
}
}

The indicated continue statement will apply to the for loop, correct?

Yes. As C99 says, "A continue statement causes a jump to the
loop-continuation portion of the smallest enclosing
iteration statement; that is, to the end of the loop body." Note
that a switch statement is not an iteration statement.

 

[CBFalconer]

Yes. As C99 says, "A continue statement causes a jump to the
loop-continuation portion of the smallest enclosing
iteration statement; that is, to the end of the loop body."
Note that a switch statement is not an iteration statement.

However it might be well to avoid the construct, both because it
may be obscure to a future reader, and it is the sort of unusual
construct that can harbor compiler bugs.

 

[Thomas Matthews]

Given the following snippet,

int i;

for( i=0 ; i < 10 ; i++ ) {
switch( i ) {
case 0: case 1:
continue; /* NB */
default:
/* do something */
}
}

The indicated continue statement will apply to the for loop, correct?

Search the web for "Duff's Device".


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Thomas Matthews

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[Alan Balmer]

However it might be well to avoid the construct, both because it
may be obscure to a future reader, and it is the sort of unusual
construct that can harbor compiler bugs.

I don't consider the general case either unusual or obscure, and
certainly wouldn't expect a compiler to mistreat it.