const-slice

Compile-time constant variants of several slice types over dynamically allocated types, implemented as slices over a fixed-capacity array (controlled by const generics).

The types in this crate will panic at compile-time if they would exceed the size of their array (currently produces a very unhelpful error - see #51999)

Examples

```rust const FIRST: &str = "mary had a"; const SECOND: &str = " little lamb.";

const BOTH: ConstString<32> = ConstString::fromstr(FIRST).withstr(SECOND);

asserteq!(BOTH, ConstString::fromstr("mary had a little lamb.")); ```