dimforge / dimforge/nalgebra

`VectorView?` type alias too restrictive?

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Dominant language
Rust
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Description

I am trying to pass parts of vectors as reference, and it seems way too convoluted for me.

MRE:
```rust
fn only_needs_ref<'a, const T: usize, const U: usize>(
vec3: VectorView<'a, i32, Const<3>, Const, Const>,
) {
println!("{}", vec3)
}

fn main() {
let vec6 = vector![1, 2, 3, 4, 5, 6];

only_needs_ref(vec6.fixed_rows(0))
}
```

I wanted to use `VectorView3`, but the types do not match:
```rust
fn only_needs_ref(vec3: VectorView3) {
println!("{}", vec3)
}

fn main() {
let vec6 = vector![1, 2, 3, 4, 5, 6];

only_needs_ref(vec6.fixed_rows(0))
}
```
```
expected struct `Matrix, _, ViewStorage<'_, i32, Const<3>, _, _, Const<3>>>`
found struct `Matrix<{integer}, Const<_>, _, ViewStorage<'_, {integer}, Const<_>, _, _, Const<6>>>`
```

Did I do something wrong? I just started with rust and nalgebra and might just have no idea how to properly do it.

------------------------------

As a side note / question:
If I want to pass the whole vector, I would type it like so:
```rust
fn only_needs_ref(vec3: &Vector6) {
println!("{}", vec3)
}

fn main() {
let vec3 = vector![1, 2, 3];

only_needs_ref(&vec3)
}
```
What is the point of the Views then? Only when I want to reference specific parts of matrizes?

Thanks

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