ANN: Pyrex 0.4.3

François Pinard pinard at iro.umontreal.ca
Tue Aug 27 20:01:22 EDT 2002


[Skip Montanaro]

>     François> Maybe Pyrex should have some generic way to declare that one
>     François> or more built-in, enumerated by name maybe, have dependably
>     François> kept their default assignment and meaning.  

> This is tough too.  Pyrex compiles modules.  What you're asking for is for a
> module author to make an invariant statement about the application as a
> whole.

(Hi, Skip!)

But Pyrex already invites authors to do this, by establishing contracts.
When I tell Pyrex `cdef char *text', I guarantee my intent about `text',
and Pyrex fills its share by producing fast access or usage to that variable.
If I do not declare a variable, Pyrex well protects its full generality.

I'm quite ready to declare that `range' and `len' have their usual meaning.
If I am not ready to this, I just will not.  But if I do, then Pyrex might
react by translating these more efficiently, and even do something special
with `for VARIABLE in range(ARGUMENTS)'.

"About the application as a whole" is hyperbolic.  Pyrex allows me to write
`cdef char *text' in global scope or just within a function.  It could allow
me to choose the scope of a `len' or `range' declaration, just the same.

If it happens that I want the equivalent of a `for from' loop in a scope
where I do not want to declare `range' as having the usual meaning, then
it would not be hurt me much to write an explicit `while' loop instead:
you know as well as I do that those cases are to be quite seldom in practice.

-- 
François Pinard   http://www.iro.umontreal.ca/~pinard





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