[m-rev.] for review: Reduce memory allocation in string.to_upper, string.to_lower.

[Julien Fischer]

On Thu, 23 Jun 2016, Peter Wang wrote:

> On Thu, 23 Jun 2016 12:06:06 +1000 (AEST), Julien Fischer <jfischer at opturion.com> wrote:
>>
>> On Mon, 20 Jun 2016, Peter Wang wrote:

...

>>>
>>>     % Convert the first character (if any) of a string to uppercase.
>>> -    % Note that this only converts unaccented Latin letters.
>>> +    % Note that this only converts letters (a-z) in the ASCII range.
>>>     %
>>
>> It may be worth extending that comment to say that base letters that lie
>> in the ASCII range in strings containing combining characters will also
>> be converted, for example:
>>
>>      io.write_string("a\u0301\n", !IO)       ==> á
>>      io.write_string(to_upper("a\u0301\n")   ==> Á
>
> Here's an attempt at the wording:
>
> to_upper
>
>    Converts a string to uppercase.
>    Only letters (a-z) in the ASCII range are converted.
>
>    This function transforms each code point individually.
>    Letters that occur within a combining sequence will be converted,
>    whereas the precomposed character equivalent to the combining
>    sequence would not be converted. For example:
>
> 	to_upper("a\u0301") ==> "A\u0301"   % á decomposed
> 	to_upper("\u00e1")  ==> "\u00e1"    % á precomposed

I think that's fine.

Julien.