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1 point by eds 6119 days ago | link | parent

So would you use the existing (C/C++) implementation of Boehm GC? If so then doesn't that make this not completely implemented in Arc? If not then that's one more piece to write (although I guess it isn't too difficult to translate code that's already been written in another language).

Yes, the assembly part of it looks difficult to me. When I look at Arc or Lisp code I don't see any way to translate that to native code. Obviously has been done, I'm just not educated on such matters.

You have a good point about the reader, I should probably add that to my proposal. And writing it in Arc would be an interesting exercise.

And can't I trust CL about tail recursion? Most decent implementations do tail recursion, right? And can't I tell people to stay away from those that don't?

But suppose I can't trust CL to do tail recursion. What am I supposed to do about it?



1 point by almkglor 6119 days ago | link

> So would you use the existing (C/C++) implementation of Boehm GC? If so then doesn't that make this not completely implemented in Arc?

And neither is Linux completely implemented in C, and C compilers written in C are not completely implemented in C, because bits and pieces of the libraries they link their code to are written in assembly.

> Yes, the assembly part of it looks difficult to me. When I look at Arc or Lisp code I don't see any way to translate that to native code. Obviously has been done, I'm just not educated on such matters.

The Lambda the Lutimate papers are a good place to start if you're interested - they include some hand-written assembly code equivalents to Scheme/Lisp code, largely function calls and prefix/suffix. Given that the most basic axioms of Arc include (fn ...) and a function call syntax, this would be quite of interest.

> But suppose I can't trust CL to do tail recursion. What am I supposed to do about it?

Use 'prog and 'go? ^^ Lambda is the lutimate!!

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1 point by sacado 6118 days ago | link

"Yes, the assembly part of it looks difficult to me. When I look at Arc or Lisp code I don't see any way to translate that to native code. Obviously has been done, I'm just not educated on such matters."

I found a good link / tutorial about how to compile a subset of Scheme to C language. The compiler is about 800 lines of Gambit Scheme (blank lines included) and even deals with tail-recursion and continuations ! (well, that's based on the lambda papers...)

No GC, but you can use Boehm and have one for free.

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1 point by stefano 6118 days ago | link

You can trust CL to do tail recursion. I'm not sure if the standard requires it but every decent implementation must provide it.

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2 points by eds 6118 days ago | link

I think I'll just say that CL-Arc is only compatible with the subset of CL implementation that do tail recursion. (Which happens to be all the implementations I would consider using anyways.)

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