Can you shrink it further?

[Andrei Alexandrescu via Digitalmars-d]

On 10/10/16 11:00 PM, Stefan Koch wrote:
> On Tuesday, 11 October 2016 at 02:48:22 UTC, Andrei Alexandrescu wrote:
>> That looks good. I'm just worried about the jump forward - ideally the
>> case c < 127 would simply entail a quick return. I tried a fix, but it
>> didn't do what I wanted in ldc. We shouldn't assert(0) if wrong - just
>> skip one byte. Also, are we right to not worry about 5- and 6-byte
>> sequences? The docs keep on threatening with it, and then immediately
>> mention those are not valid.
>>
>> [ ... ]
>>
>> Andrei
>>
>
> If you want to skip a byte it's easy to do as well.
>
> void popFront3(ref char[] s) @trusted pure nothrow {
>    immutable c = s[0];
>    uint char_length = 1;
>    if (c < 127)
>    {
>    Lend :
>      s = s.ptr[char_length .. s.length];
>    } else {
>      if ((c & b01100_0000) == 0b1000_0000)
>      {
>        //just skip one in case this is not the beginning of a code-point
> char
>        goto Lend;
>      }
>      if (c < 192)
>      {
>        char_length = 2;
>        goto Lend;
>      }
>      if (c < 240)
>      {
>        char_length = 3;
>        goto Lend;
>      }
>      if (c < 248)
>      {
>        char_length = 4;
>        goto Lend;
>      }
>    }
>  }
>

Affirmative. That's identical to the code in "[ ... ]" :o). Generated 
code still does a jmp forward though. -- Andrei