Description of slice is misleading

[slengfeld]

The chapter about slices https://github.com/nrc/r4cppp/blob/master/arrays.md#slices uses wrong comparisons. It states

A slice in Rust is just an array whose length is not known at compile time.

But the rust documentation about slices says https://doc.rust-lang.org/std/slice/

A dynamically-sized view into a contiguous sequence, [T].

So a rust slice is similar to a C++ std:span https://en.cppreference.com/w/cpp/container/span and not similar to a rust array (a value) or to an C/C++ array (only a pointer).