There’s also Dutch, where ‘ij’ sort-of is a single letter, so capitalizing “ijs” yields “IJs” (<a href="https://en.wikipedia.org/wiki/IJ_(digraph)#Capitalisation" rel="nofollow">https://en.wikipedia.org/wiki/IJ_(digraph)#Capitalisation</a>)<p>Unicode has separate code points for those, but their use is discouraged.
I know nothing about Rust, and couldn't grok most of what was said in the post, but I'm curious. Is this all just to please the type system, and will it result in efficient code as if I did the following in C (for some implementation of to_uppercase())?<p><pre><code> c[0] = to_uppercase(c[0]);</code></pre>