[ZODB-Dev] oids, numbers, hex and 8-byte strings

[Chris Withers]

Tim Peters wrote:
> You found ZODB.utils, which was a sensible place to look.  I don't really
> understand how you found ZODB.utils but didn't manage to find p64, because
> p64 is the first function in the file.

Because its name means nothing to me...

>>I guess p64 needs documenting,
> 
> I think its docstring is reasonably clear:
> 
>     def p64(v):
>         """Pack an integer or long into a 8-byte string"""

Yes, but for that to be meaningful, you have to know that:

- 0xSomething is an integer or long (it read "hex number" in my head"

- oids are 8-byte strings

Neither of things that sit in my brain :-(

> In addition to that, it would be helpful to have a tutorial overview
> "somewhere" explaining that FileStorage oids are 8-byte strings.  I don't
> know where to put that so that people would find it, though.  For example,
> where would you have found it?

howtoturnnumbersintooids.txt :-S

I dunno, readme.txt? reference.txt?

>>and maybe a better name?
> 
> 
> Many ZODB users already know this, and there are references to p64 on user
> web pages.  For example,
> 
>     http://www.zopezone.com/discussions/general/00000168
> 
> shows how to do what you started out to do:
> 
> 
>>>>from Zope.Startup.run import configure;configure('zope-8000/zope.conf')
>>>>from Zope import app; root = app()
>>>>from ZODB.utils import p64
>>>>o = root._p_jar[p64(0x277FEL)]
>>>>o
> 
> OOBucket([('566', -1920968609), ...])

Indeed, Google failed me *sigh*

> I don't want to break pages like that, so the current name has to remain.

Absolutely.

> It would be possible to add an alias.  I'm -0 on that (would violate TOOWTDI
> in exchange for ... well, not sure it would really help anyone anyway).

TOOWTDI?

It might help some people (would have helped me ;-) ) and would it hurt 
anyone?

cheers,

Chris

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