struct having name like MyData_T_int

[impopular-guy]

I purposefully named the struct MyData_T_int to see what happens. This fails to run but C code is generated without errors. It seems like the definition of MyData[int] is overwritten by MyData_T_int, so there ends up only one struct definition which causes the error.

struct MyData[T]{
    a T
}

struct MyData_T_int{
    b string
}

fn main() {
    d1 := MyData[int]{12}
    println(d1)
    d2 := MyData_T_int{'qwerty'}
    println(d2)
}

The code runs if fields of both struct have same name and same type or type is castable(like int to f32).

How should such a problem be solved? I tried searching the internet but didn't find anything. I am not very knowledgeable about compilers and not sure how other languages solve such an issue?

Possible soln that come to my mind 1) not allow such name 2) add some suffix like MyData_T_int_suffix 3) ignore?

Btw, great language, keep up the great work.

[JalonSolov]

Interesting way of hacking the compiler. :-)

1. Not sure how the name could be prevented. V wouldn't know there was a problem until backend code generation time.

2. This might work, but we would have to study the effects.

3. No, I don't think it should be ignored, since it can obviously cause problems with name collisions.

[i582]

Thanks for the interesting find!
I think all generated names should be prefixed with __ which should be forbid for user code.

[JalonSolov]

... except some C compilers treat variables with __ prefix differently than regular variables.

[i582]

... except some C compilers treat variables with __ prefix differently than regular variables.

ok, suffix

[medvednikov]

In the original V, _ was banned in struct names for this reason. Also nice for the one way rule.

I wish I kept this rule.

[Delta456]

I mean we can simply change the C code generation for this. There is no need to ban using _.

[spytheman]

How about just banning _T_ in struct names?

Edit: it would need to be a ban for _CAPITAL_, not just _T_ .

[Delta456]

How about just banning _T_ in struct names?

Edit: it would need to be a ban for _CAPITAL_, not just _T_ .

I feel this is quite restricting and the user should be able to name what they want too.

[Wajinn]

It's better to know about such hacks, even if inconvenient, than to not know. This way they can be dealt with in some way.