Re: Add CASEFOLD() function.

On 16.12.24 18:49, Jeff Davis wrote:
> One question I have is whether we want this function to normalize the
> output.
>
> I believe most usecases would want the output normalized, because
> normalization differences (e.g. "a" U+0061 followed by "combining
> acute" U+0301 vs "a with acute" U+00E1) are more minor than differences
> in case.

Can you explain this in further detail? I don't quite follow why this
would be required.

> Of course, a user could wrap it with the normalize() function, but
> that's verbose and easy to forget. I'm also not sure that it can be
> made as fast as a combined function that does both.
>
> And a follow-up question: if it does normalize, the second parameter
> would be the requested normal form. But to accept the keyword forms
> (NFC, NFD in gram.y) rather than the string forms ('NFC', 'NFD') then
> we'd need to also need to add CASEFOLD to gram.y (like NORMALIZE). Is
> that a reasonable thing to do?

That's maybe one reason to keep it separate.

Another might be that's not entirely clear how this should work in
encodings other than UTF-8. For example, the normalized string might
not be representable in the encoding.