toString refactor in druntime

[Steven Schveighoffer via Digitalmars-d]

On 10/29/14 6:03 AM, Kagamin wrote:
> struct Sink
> {
>     char[] buff;
>     void delegate(in char[]) sink;
>
>     void write(in char[] s)
>     {
>        auto len=min(s.length,buff.length);
>        buff[0..len]=s[0..len];
>        buff=buff[len..$];
>        const s1=s[len..$];
>        if(s1.length)sink(s1);
>     }
> }
>
> override void toString(ref Sink sink) const
> {
>     value.toString(sink);
>     sink.write("[");
>     len.toString(sink);
>     sink.write("]");
> }

This would require sink to write the buffer before it's first call, 
since you don't track that.

Wouldn't it be better to track the "used" length in buff directly so 
write can handle that?

Not a bad idea, BTW.

-Steve