Pyrex
The Pyrex language (http://www.cosc.canterbury.ac.nz/~greg/python/Pyrex/) is often the most convenient way to write extensions for Python. Pyrex is a large subset of Python, with the addition of optional C-like types for variables: you can automatically compile Pyrex programs (source files with extension .pyx) into machine code (via an intermediate stage of generated C code), producing Python-importable extensions. See the above URL for all the details of Pyrex programming; in this section, I cover only a few essentials to let you get started with Pyrex.
The limitations of the Pyrex language, compared with Python, are the following:
No nesting of
defandclassstatements in other statements (except that one level ofdefwithin one level ofclassis okay, and indeed is the proper and normal way to define a class’s methods).No
import *, generators, list comprehensions, decorators, or augmented assignment.No
globalsandlocalsbuilt-ins.To give a class a
staticmethodorclassmethod, you must firstdefthe function outside the class statement (in Python, it’s normallydefed within the class).
As you can see, while not quite as rich as Python proper, Pyrex is a vast subset indeed. More importantly, Pyrex adds to Python a few statements that allow C-like declarations, enabling easy generation of machine code (via an intermediate C-code generation step). Here is a simple example; code it in source file hello.pyx in a new empty directory:
def hello(char *name): return "Hello, " + name ...
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