Re: [Pytables-users] Unbound nodes. [was: ( __getattr__ vs. __getitem__ (Natural naming)]

[Ivan V. i B. <iv...@ca...>]

On Tue, Jan 25, 2005 at 08:00:28PM +0100, Norbert Nemec wrote:
> Am Dienstag, 25. Januar 2005 17:39 schrieb Francesc Altet:
[...]
> The usual behavior of object in python is, that the constructor creates a=
n=20
> object, but does not link any handle to it, so if you don't preserve the=
=20
> reference that the constructor returns, the object is dead immediately.
[...]

However, one could see that PyTables nodes have the additional
requirement that they must belong in an HDF5 file.  A nice parallelism
can be made with UNIX-like filesystems.  There, files and directories do
not properly belong to a directory, but are accessed via their inode
instead.  However, the user is not able to create files at the inode
level, but has to use additional functions (like creat(), mkdir(),
mknod()...) to create them and instantly (i.e. atomically) place them in
some directory.  This avoids creating files that are not accessible
through the file system path hierarchy.

    Giving the user the opportunity to go straight to Node constructor
calling would be like letting Unix users create files that are never
bound to a directory.  It might seem more elegant sometimes, but it
breaks the hierarchical concept by allowing a kind of =E2=80=9Cparallel
hierarchies=E2=80=9D.

    Having said that, I keep the opinion that node creation, removal and
renaming should belong in Group methods and nowhere else.  Bye!

--=20
Ivan Vilata i Balaguer   >qo<   http://www.carabos.com/
       C=C3=A1rabos Coop. V.  V  V   Enjoy Data
                          ""