Competing with C in a simple loop

Christopher Done chrisdone at
Fri Dec 23 15:08:44 UTC 2016

Oh, you're correct! It's unable to parse that file! The files is a test
suite file from the XML spec, I guess hexml is unable to parse this one.
I'll remove it from my benchmark suite in favor of something that does


On 23 December 2016 at 14:55, Harendra Kumar <harendra.kumar at>

> On 23 December 2016 at 03:23, Christopher Done <chrisdone at>
> wrote:
>> But if you scroll down the README to the 182kb file example, you see that
>> hexml takes 33us and xeno takes 111us. That's surprising to me because I'm
>> doing just a walk across a string and hexml is doing a full parse. It's
>> written in C, but still, 3x faster AND doing allocations and more work.
> hexml being a full parser might fail, on the other hand your program
> unconditionally walks the bytestring. Are you sure hexml is actually
> completing and not aborting or short-circuiting because of a parse error or
> some other error? In all other data points xeno is taking much less time
> than hexml except this one. So I am suspecting it could be a problem with
> the input, making hexml fail silently. I see that the file used on this
> data point has japanese characters, maybe hexml is not able to handle those?
> -harendra
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