On Wednesday, 6 September 2017 at 05:23:47 UTC, Ali Çehreli wrote:
On 09/05/2017 07:05 PM, Psychological Cleanup wrote:
> Nesting static foreach and using enum has latent problem.
>
> static foreach()
> static foreach()
> {
> enum A = ;
> }
>
> compiler complains because A is defined multiple times by the
outer most
> foreach.
That's understandable as there are multiple As dropped into
code.
> To fix this
>
> static foreach()
> static foreach()
> {
> {
> enum A = ;
> }
> }
>
> But then compiler complains about unexpected { if in a scope
where
> normal {}'s are not expected.
Can you demonstrate with compilable code? Doing what you
describe works for me:
void main() {
static foreach(i; 0 .. 3)
static foreach(j; 0 .. 3)
{
{
enum A = i * j;
}
}
}
Ali
Yes, but I said you can't do that. Put the static foreaches
outside main in to a block where one can't simply do {} and it be
valid.
You see, the point is that
static foreach
static foreach
{
}
works at the module level
static foreach
static foreach
{
enum a = ;
}
fails because of multiple a's
so
static foreach
static foreach
{
{
enum a = ;
}
}
to solve that(which, in your given example, works inside main)
but fails at the module scope because the { }'s we used to solve
the first problem created a new problem. The two methods are
mutually exclusive but both are required.
Sure, I could wrap stuff around a function, but what if I'm using
them for code generation inside a class? I have to use the extra
{ } to prevent the enum error but then I get a new error about
the { }.
class X
{
static foreach
static foreach
{
// fails, multiple a
enum a = ; // part of class generation code like
generating functions
}
}
class X
{
static foreach
static foreach
{
// fails, { } block inside a class.
{
enum a = ; // part of class generation code like
generating functions
}
}
}
it works fine if we use it in a function because we can have { }
in functions without problems.
Do you not see the contradictory nature? { } required but { }
forbidden.
