Roy Smith schrieb:
In article <[EMAIL PROTECTED]>,
"Diez B. Roggisch" <[EMAIL PROTECTED]> wrote:
Also, I thought that part of the python philosophy was to allow any
sort of object in a list, and to allow the same methods to work with
whatever was in list.
Not really. When the usual argument about the existence (and
justification) of lists & tuples comes along, one common distinction is
that
- tuples contain arbitrary object of varying types, so they are kind
of "records"
- lists should contain uniform objects.
I see absolutely nothing wrong with lists of heterogenous types. Or, for
that matter, iterators which generate heterogeneous types. Here's some
perfectly reasonable examples (equally applicable to lists or iterators):
* The tokens parsed out of a file (ints, floats, identifiers, keywords,
various kinds of punctuation, etc)
* The entries in a unix directory (plain files, directories, symlinks,
special files, named sockets, etc)
* The vehicles going through a toll booth (cars, trucks, motorcycles)
I don't see any reason you shouldn't be able to build lists of those things.
When I wrote "uniform" I meant objects of the same kind. So for example
subclasses are of course ok. And all of your examples are these: I want
a Token-object, keeping file-location and possibly original string
representation. The same goes for files - they are simply strings, their
properties determined using stat-calls. And vehicles are... vehicles. So
I'd create a common base-class for them, or made them at least behave
proper through duck-typing. Which - for the case at hand - might include
creating a __cmp__-method, based on horsepower or price-tag or...
Diez
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