[i, j] is considered a refutable pattern for [int, ..2]

[kmcallister]

let f: |[int, ..2]| -> int = |[i, j]| i+j;

produces

foo.rs:2:35: 2:41 error: refutable pattern in function argument
foo.rs:2     let f: |[int, ..2]| -> int = |[i, j]| i+j;
                                           ^~~~~~

But

for [i, j] in Some([1,2]).move_iter() {}

is fine.

rustc 0.11.0-pre (fbd8f4a 2014-05-15 08:36:50 -0700)
host: x86_64-unknown-linux-gnu

[huonw]

The reason for for working is it uses match internally, which was changed to recognise fixed-length vectors properly at some point, but let does not. (Dupe of #7784.)