[pypy-dev] Re: [pypy-svn] r8642 - pypy/dist/pypy/objspace/std

[Christian Tismer]

ludal at codespeak.net wrote:

> Author: ludal
> Date: Thu Jan 27 18:06:26 2005
> New Revision: 8642
> 
> Modified:
>    pypy/dist/pypy/objspace/std/stringobject.py
> Log:
> keep a cache of the hash value of strings like CPython does

Hi!

I think it is a fine idea to do the hash cache.
Just a comment...:

> Modified: pypy/dist/pypy/objspace/std/stringobject.py
...

>  def hash__String(space, w_str):
> -    return W_IntObject(space, hash(w_str._value))
> +    w_hash = w_str.w_hash
> +    if w_hash is None:
> +        w_hash = W_IntObject(space, hash(w_str._value))
> +        w_str.w_hash = w_hash
> +    return w_hash

I don't see the point why the hash should be stored as a wrapped
value. IMHO, the main use of the hash is inside of dict objects.
Wouldn't it make more sense to cache the unwrapped value, since
we (as I think) do the hashing in a dict with an unwrapped
integer, anyway?
It is also more conformant with CPython, where the hash is
an internal implementation detail.

Maybe I just missed something, so anyway - good night!

(Ludovic, I don't have your email contact)

cheers - chris
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