[Haskell-cafe] Array, Vector, Bytestring

[silvio]

> Just to clarify for those on the sidelines, the issue is duplication of
> implementation details, rather than duplication of functionality?

Well to me, that is not the main issue. The main issue is that you have 
to study all of them and depending on which libraries you want to use 
have to convert between them, which could be expensive and is definitely 
annoying.

I made a few simple benchmarks comparing the three libraries you can 
find the code attached.

this is compiled with -O2

# simple sum of 1000000 Word8 elements

Unboxed Vector           1.114060 ms
Storable Vector          795.1207 us
Primitive Vector         1.116145 ms

ByteString               9.076256 ms

array library has no fold or sum function

# simple sum of 1000000 more or less randomly chosen elements

Unboxed Vector (unsafe)    33.74364 ms
Storable Vector (unsafe)   50.27273 ms
Storable Vector (safe)     67.01634 ms
Primitive Vector (unsafe)  56.29919 ms

ByteString (unsafe)        19.29611 ms
ByteString (safe)          18.29065 ms

UArray (safe)              46.88719 ms
unsafe does not exist for array

So Unboxed can be better than Storable but doesn't need to be.
Also, which implementation is faster depends very much on the problem at 
hand. And array is just missing half the needed features.

Silvio
-------------- next part --------------
A non-text attachment was scrubbed...
Name: Array.hs
Type: text/x-haskell
Size: 2738 bytes
Desc: not available
URL: <http://www.haskell.org/pipermail/haskell-cafe/attachments/20130604/5fdfed6f/attachment.hs>