<div dir="ltr">Indeed. Type annotations, inlining, and writing monomorphic functions are quite handy for making tight inner loops.<div><br></div><div style>As are making sure there are no bad branch predictors, that memory locality quality is superb, and that if possible SIMD instructions, and cache hierarchy aware parallelism.</div>
<div style><br></div><div style>At the same time, these are not AND should not be the concerns of normal end user codes. Tuning tight inner loops is a nontrivial task engineering task in any language, providing generic apis by default does not prevent writing monomorphic versions as needed.</div>
<div style><br></div><div style>Unless you have an example where for normal application code there will be a significant constant factor difference in performance with the proposed changes, i don't understand your contention :) </div>
<div style><br></div><div style>Also, for those sorts of problems as you point at, what is an example that can't be resolved with the inlinable + specialize pragmas, that wouldn't otherwise be a problem anyways?</div>
<div style><br></div><div style>Anyways, I do care about performance, but small constant factors are cheaper to fix if need be than are the constant factors in better base api. Anyone who's privy to my work over the past few months know I quite literally spend all my time thinking about memory locality :) </div>
<div style><br></div><div style>cheers</div><div style>-Carter</div></div><div class="gmail_extra"><br><br><div class="gmail_quote">On Sun, May 26, 2013 at 5:21 AM, Malcolm Wallace <span dir="ltr"><<a href="mailto:malcolm.wallace@me.com" target="_blank">malcolm.wallace@me.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div class="im"><br>
On 21 May 2013, at 06:06, Carter Schonwald wrote:<br>
<br>
> lets see what concerns there are<br>
><br>
> 1) will any code break? Nope!<br>
</div><div class="im">> 2) does the change make learning the language more challenging? No.<br>
<br>
</div>One concern that is conspicuously missing from your list is<br>
<br>
3) performance. Will my code get slower, because it now has many more class dictionaries, requiring new runtime indirections?<br>
<br>
I quote from the GHC manual:<br>
<br>
"Overloaded functions are not your friend:<br>
Haskell's overloading (using type classes) is elegant, neat, etc., etc., but it is death to performance if left to linger in an inner loop."<br>
<br>
Regards,<br>
Malcolm<br>
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