esoteric question about dict keys (Re: age of Python programmers)

[Alexis Roda]

This is my first message to the list, so I'll present myself and add my 
contribution to the "age of python programmes" thread.

My name is Alexis Roda, I'm 36 - 7/365 years old, I started programming 
with python two years ago, mainly because I started playing with zope. 
At first I was a reluctant Perl converted, although initially I hated 
python (well, I hated zope wich make me hate python) now I'm in love 
with both python and zope. I started programming at 15 with a Casio 
calculator (a kind of assembler), then an Amstrad CPC464 (Basic), a 
Macintosh Plus (Pascal, C, Lisp, assembler) and finally come to the 
PC/Linux world (assembler, C, C++, Perl, bash scripting, elisp and python).

Now the question. In "normal" dicts its not possible to use dictionaries 
(nor other kinds of mutable objects) as keys, if I undersand correctly 
this is a technical requirement. If I write my own dictionary-like 
object, on wich the mutability of the keys is not a technical issue, is 
considered blasphemous the use of dicts as keys? For example, querying 
an SQL table can be partially modelled as a dictionary access:

table[pkey_value] gives a record for this primary key

table[{'somefield':somevalue}] returns all the records where 
somefield=somevalue

or is preferable to define a query() method for these uses and restrict 
__getitem__ to mutable objects for the sake of consistency?




TIA
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<>               Ojo por ojo y el mundo acabara ciego
/\ Alexis Roda - Universitat Rovira i Virgili - Reus, Tarragona (Spain)
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