Typed Python?

[Fernando Perez]

Paul Prescod wrote:

> To put it another way: Jarek complains that static typing would destroy
> the "fun". I think he means Python's flexibility. A type inferencer
> removes the need to declare types but a statically type-inferenced
> language is still statically typed. It will still be strict about type
> usage.

I am one who would really like _optional_ static typing information to be
available in python, but for different reasons than the usually requested here:
performance.  My field is scientific computing, and when you are inside a
simple for loop, manipulating arrays of homogeneous data, the overhead of
python's dynamicism is a killer.  Obviously what ends up happening is that we
rewrite those parts of our codes in C/C++/Fortran, but it would be great to be
able to simply tell python the types of the variables and have it not do any of
its dynamic runtime checks.

I do not believe in static typing as a compile-time 'feature': I've grown to
feel that all the supposed benefits of static typing can indeed be achieved
with proper testing, and the _huge_ gains in flexibility and productivity one
gets from python's type model are something I don't want to do without.

But for tightly constrained code that needs to run as fast as possible, without
repeating any unnecessary work (such as type detection), having an option to
declare type information would be a huge boon.

Cheers,

f