bug#61726: [PATCH] Eglot: Support positionEncoding capability

[Augusto Stoffel]

On Fri, 24 Feb 2023 at 13:27, Eli Zaretskii wrote:

>> > As discussed, position-bytes is incorrect.  You should instead do
>> > something like
>> >
>> >   (length (encode-coding-string
>> >            (buffer-substring-no-properties (point)
>> >                                            (line-beginning-position))
>> >            'utf-8-unix t))
>> 
>> But it is incorrect only if the buffer contains characters outside of
>> the Unicode range, right?  If that happens, we already lost, because a
>> few steps later we will serialize the buffer text as JSON to send it to
>> the server:
>
> Why should one part of the code depend on what another part does?  In
> my book, each part should do its job, and do it right.

Arguably both implementations are wrong, and the correct one should
produce an error if the buffer substring cannot be converted to valid
UTF-8.

Between two “wrong” but perfectly functional implementations, I'd choose
the more efficient one, because efficiency actually matters in this
case.  So which one is more efficient?