== Quote from bearophile ([email protected])'s article
> When I have suggested to add "computed gotos" (similar to the ones of GCC) to
> D,
Walter has answered that they need some work to be implemented, and they have
limited usefulness, almost only to optimize interpreters.
> But:
> - D is a system language, so writing interpreters is an important application
> of it.
> - I have found GCC computed gotos useful to speed up some of my code. Recently
even the CPython has introduced their usage in the main interpreter loop.
> - The GCC implementation of computed gotos is not standard for C and other
compilers may not understand it (to solve this trouble in GNU C code you need to
disable pieces of code, and this is less easy to do in D).
> So even if computed gotos are not going to be implemented in DMD I suggest to:
> 1) Invent a syntax to represent and use them (probably the GCC syntax is good,
because it's already known in C).
> 2) Make DMD understand this syntax, but refuse it at compile time (because DMD
doesn't support computer gotos).
> 3) Define a new standard Predefined Version, like "computed_goto" or
"Computed_goto" or something similar, that is defined if a D compiler supports
them (so DMD doesn't define it), that allows to disable the code that contains
the
computed goto if a compiler doesn't support them.
I don't think this feature really warrants a new keyword.
Since we already have:
const var = 42;
switch (x) {
case var:
...
break;
}
Would only make sense to do the same for goto's.
goto *ptr;
Something that *would* warrant perhaps a new keyword would be non-local gotos,
but
it's usefulness is very negligible...
Regards
Iain
