From: Robert Feldt <feldt@...>
Date: 2001-11-29T01:21:48+09:00
Subject: [ruby-talk:26817] Re: .NET possibilities for Ruby

Hi,

I haven't studied .NET/MS-IL/CLR very much but I read ActiveState's
white paper on Python for .NET (PFN). Some misc quotes from the paper that
are somewhat related to a Ruby for .NET project:

* "The current state of the [PFN] compiler and the runtime systems shows
that it is possible to have compiled Python programs fully supported
within the .NET  framework. Most of the basic infrastructure is in place, 
with full bi-directional cross-language support (i.e., Python can inherit 
or call objects created in other languages, and other languages can
inherit from or call objects created in Python)."

* "The speed of the current system is so low as to render the current
implementation useless for anything beyond demonstration purposes.  This
speed problem applies to both the compiler itself, and the code generated
by the compiler. "

* "The Python for .NET compiler is written using CPython.  It compiles
Python source code, and uses the .NET Reflection::Emit library to generate
a .NET assembly.  The  COM Interoperability features of .NET are used to
access the Reflection::Emit library."

* "Although support for basic classes works fine, there are a number of
areas where Python and .NET semantics collide - the most obvious being
multiple inheritance (supported by Python, but not by .NET).  Other more
subtle examples include the ability of a Python subclass to avoid calling
a base-class constructor, or to reference self (the moral equivalent of
this in C#) before calling any constructors at all."

* "Due to Python's dynamic nature, there are some Python features that are
difficult to map into .NET semantics.  A simple example is the ability for
a Python object to add attributes at runtime - although no declaration or
other reference to the attribute can be seen by source code analysis,
reference to the attribute will succeed at runtime.  Python provides many
other ways to change object behaviour at runtime that are not captured by
.NET."

I'd also like to note that David Simmons says he's found a way to get good
interoperability between .NET and a dymically typed, OO script language
but there aren't any details out yet...

Regards,

Robert