The `~str` type is not long for this world as it will be superseded by the
soon-to-come DST changes for the language. The new type will be
`~Str`, and matching over the allocation will no longer be supported.
Matching on `&str` will continue to work, in both a pre and post DST world.
The `print!` and `println!` macros are now the preferred method of printing, and so there is no reason to export the `stdio` functions in the prelude. The functions have also been replaced by their macro counterparts in the tutorial and other documentation so that newcomers don't get confused about what they should be using.
Code like this is fixed now:
```
fn foo(p: [u8, ..4]) {
match p {
[a, b, c, d] => {}
};
}
```
Invalid constructors are not reported as errors yet:
```
fn foo(p: [u8, ..4]) {
match p {
[_, _, _] => {} // this should be error
[_, _, _, _, _, .._] => {} // and this
_ => {}
}
}
```
Issue #8311 is partially fixed by this commit. Fixed-length arrays in
let statement are not yet allowed:
```
let [a, b, c] = [1, 2, 3]; // still fails
```