[MLton] F# - the future of ML?

[skaller]

On Tue, 2006-12-19 at 01:29 +0100, Wesley W. Terpstra wrote:
> I realize this is a bit off-topic, but wanted the opinions of the  
> people on this list. :-)
> 
> I ran into F# over the weekend and was quite impressed!

> Thoughts?

F# stole the Felix model of code generation :)

Felix is built on C/C++ the same way as F# is on .NET,
and for the same reasons.

[NekoML is also built that way, on top of Neko 
which has its own VM]

The downside is: you're stuck with what might be an
inappropriate object and type model.


For those that don't know: F# defines primitives in terms
of CLR machine instructions. It therefore has direct,
native, access to the .NET platform.

Felix defines its primitives with snippets of C++ code,
such as:

	fun print[t]: t = "cout << $1;";

This model, which allows embedding of the target language
directly into the source language makes for a very powerful
and easy to develop translator .. although the embeddings
may be unsafe (as with any binding). However the 'FFI' here
is mainly a type wrapping -- the native object model is used
so there is no need for run time glue logic.

So .. if you tried to do this with Mlton and C you'd be stuck
unable to use a continuation passing model, or implement the
user space high performance threading, since C doesn't really
support that.

Felix makes that compromise for compatibility, availability
of libraries, and easy wrapping for end users etc, but has
the luxury of being designed from scratch to do so.

Mlton on the other hand wants to implement SML so doen't
have the luxury of designing the language to suit the
target object and type model.

So my guess is that this model is useful when your
primary goal is compatibility with a target model,
but not so good when your goal is compatibility with
a standardised source model.


-- 
John Skaller <skaller at users dot sf dot net>
Felix, successor to C++: http://felix.sf.net