Re: [ats-lang-users] New to ATS

[Hongwei Xi <hw...@cs...>]

On Sun, 14 Mar 2010, Rouan van Dalen wrote:

>>Hi everyone.
>>
>>I have stumbled onto ATS because I am interrested in non-main stream programming languages and love to try
>>out interresting ones.
>>
>>As I have no experience in ATS and I can't find too many blogs about it, I have a few questions.

Good. Let me try to address your questions. Given that I am the 
principal designer and implementer of ATS, I have to say that I
am a bit biased :)

>>1. Would you say that ATS is ready for writing applications outside the academic environment?

Yes!

So far, the largest software written in ATS is ATS/Anairiats, the current 
compiler for ATS. It consists of more than 90K lines of code.

Given that ATS uses native data representation as C, it is straightforward
to port C library to ATS. Given that ATS code is compiled to C first, 
linking with C library code is a no-brainer.

I myself even use ATS for scripting, graphics, slide presentation, etc.
I see no problem at all writing real applications in ATS.

>>2. How expressive is its type-system, compared to say OCaml / Haskell?

A great deal more expressive. It is hard to quantify this. The very 
strength of ATS is in its type system. It may take years of learning for 
one to truly unleash the power of the types in ATS (it takes a lot of
time for one to use C++ effectively, too :))

>>ATS seems like a language where I can write in a functional style (which I really like) and it seems
>>that ATS can be used to write fairly efficient code.
>>
>>I am looking to invest some substantial time into ATS if I can use it for more practical, real-world
>>programming.

I have never worked in the industry, so I don't really have a clear idea 
as to what a real-world application looks like. However, I have read a lot
of open-source code, and can easily imagine to implement such code in ATS;
actually, I can often easily imagine to do a better implementation in ATS
by taking advantage of the type system of ATS.

>>I am looking for a good, efficient language to write a compiler for my own programming language.
>>I am hoping that ATS will be this language.  Can anyone advise if ATS is a good language for
>>this purpose and if there are any specific features of ATS that would come in handy for writing
>>a compiler in ATS.

It is hard to say because I don't know what your language is like.
In general, writing a compiler in ATS is most like writing a compiler
in a language like ocaml. However, you can certainly do more 
verification by making use of dependent types and linear types in ATS.
If you need, I will be happy to point to you some resources for writing a
compiler in ATS. If you have further questions, I will be happy to address
(to the extent I can).

--Hongwei

Computer Science Department
Boston University
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