What do you think of this control block?As a new language feature?
do
{
FILE f = fopen("file.txt", "r");
if (f == NULL) quit; /*goes to else part*/
/*success here*/
for (int i =0; i < 10; i++){
...
if (error) quit;
}
}
else
{
/*some error*/
}
I think 'do {}' would be confused 'do {} while' (a parser - or a human - won't know this isn't a loop until the 'else' is seen. And then there's a possibility that that 'else' belongs to an 'if' but an omission or inclusion of a braces has screwed things up.
Perhaps a new keyword ('try' maybe) is better.
You'd also need to specify how nested do-else blocks will work. Or will 'quit' (so you have a new keyword anyway) only work at this level?
What about chained versions: do {} else do {} else ...; I guess 'quit' will just go to the next else block rather than quit the whole chain?
Note that this can be emulated in C now using:
if
{
goto quit001;
}
else
{quit001:
}
Perhaps what C needs is a way to do that jump without an explicit goto:
if
{
quit001;
}
else
{quit001:
}
You can require that such jumps can only go forwards.
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