[DSLX] In struct parametrics as is not constexpr-compatible

[dank-openai]

Describe the bug

Try to build this:

pub struct foo<IS_SIGNED: u32 , NUM_BITS: u32> {
    data: xN[IS_SIGNED as u1][NUM_BITS], 
}

#[test]
fn test_instantiate_foo() {
    let _ = foo<u32:0, u32:1> { data: u1:0};
}

observe error:

Could not evaluate dimension expression `IS_SIGNED as u1` to a constant value.

To Reproduce
Use code above, try to compile.

Expected behavior
I expect that I can cast a u32 to a u1 to define a type. That is, I expect that casting is constexpr-compatible.

More comments
I tried another way of accomplishing the same thing:

pub struct foo<IS_SIGNED: u32 , NUM_BITS: u32, sign:bool = {IS_SIGNED > u32:0} > {
    data: xN[sign][NUM_BITS], 
}

#[test]
fn test_instantiate_foo() {
    let _ = foo<u32:0, u32:1> { data: u1:0};
}

and when I try to build and test:

Error: INVALID_ARGUMENT: Cannot convert expression to parametric: IS_SIGNED > u32:0

let's try again, but same error (i.e., Cannot convert expression to parametric):

pub struct foo<IS_SIGNED: u32 , NUM_BITS: u32, sign:bool = {if IS_SIGNED > u32:0 {true}else{false}} > {
    data: xN[sign][NUM_BITS], 
}

[cdleary]

@dank-openai struct parametrics are different from function parametrics, as is fine for constexpr in a general sense it's just a problem in the context of struct parametrics.

[dank-openai]

@dank-openai struct parametrics are different from function parametrics, as is fine for constexpr in a general sense it's just a problem in the context of struct parametrics.

I see. Thanks for the explanation.