Unhelpful parser error trying to get an associated item from an array type the intuitive-but-wrong way

[scottmcm]

Example asked about on IRC:

[f32; 2]::deserialize(deserializer).map(|arr| Location { lat: arr[0], lon: arr[1] })

Simple repro:

fn main() {
    let a = [1, 2, 3];
    let _ = [i32; 3]::clone(&a);
}

Current error:

error: expected one of `.`, `;`, `?`, or an operator, found `::`
 --> <anon>:3:20
  |
3 |     let _ = [i32;3]::clone(&a);
  |                    ^^ expected one of `.`, `;`, `?`, or an operator here

The direct solution (<[f32; 2]>::deserialize) is non-obvious and hard to search for, so the compiler could be particularly helpful here.