[racket-users] Re: Self evaluating Racket Interpreter

[circularballs]

I forgot to mention that for some reason, using the builtin foldl doesn't work 
but if I define it myself separately, then it works. 

  (define (foldl proc init lst)
(cond
  ((null? lst) init)
  (else (foldl proc (proc (car lst) init) (cdr lst)

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[racket-users] Re: Self evaluating Racket Interpreter

[circularballs]

Thanks Matthias. I should have read the error message more carefully. 

For anyone who is interested, it has nothing to do with cons or mcons or 
quotes. There was a mistake in interpreter.rkt.

If you'd like to try finding it yourself, then stop reading.
...
...
...
...
...
...
...
...
...
...
Here's the fix. In interpreter.rkt, under the definition of myeval, in the case 
of a let expression, it should have been:
  [(eq? (car expr) 'let)
   (eval-sequence (cddr expr)
  (extend-env
   (map first (second expr))
   (eval-args (map second (second expr)) env)
   env))]




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[racket-users] Re: Self evaluating Racket Interpreter

[circularballs]

I am somewhat reluctant to use structures as I want to keep the interpreter as 
minimal as possible. Also, I'm not familiar enough with the semantics of frames 
to implement it in interpreter.rkt.

With regards to mcons being different from cons, Oscar Lopez has suggested that 
in stackoverflow. So, I re-implemented the interpreter in r5rs so that set-car! 
and set-cdr! are available and I wouldn't need to use mcons. I've attached the 
files here.

I still got an error
; application: not a procedure;
;  expected a procedure that can be applied to arguments
;   given: (mcons 'expr (mcons 'env))
;   arguments...: [none]

It looks like it still has something to do with mcons. I suspect that this 
might have something to do with Racket's implementation of r5rs? Again, this 
might be completely wrong but I don't know how to determine the cause. 

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interpreter-r5rs.rkt
Description: Binary data


interpreter-r5rs-self-evaluate.rkt
Description: Binary data

Re: [racket-users] Self evaluating Racket Interpreter

[circularballs]

On Tuesday, May 2, 2017 at 2:03:23 AM UTC+8, Jens Axel Søgaard wrote:
> I recommend you change your representation to structures.
> 
> 
> See new answer:
> 
> 
> http://stackoverflow.com/a/43723966/23567
> 
> 
> 
> /Jens Axel
> 
> 
> 
> 
> 
> 
> 2017-05-01 19:03 GMT+02:00  :
> I posted this question on stackoverflow but have not found an answer yet. 
> https://stackoverflow.com/questions/43476080/self-evaluting-racket-interpreter
> 
> 
> 
> I've been trying to write a Racket interpreter that can interpret itself.
> 
> 
> 
> interpreter.rkt contains the code for the interpreter. It is pretty standard. 
> Then, in interpreter-self-evaluate.rkt, I
> 
>     1. import interpreter.rkt,
> 
>     2. copy paste the code from interpreter.rkt and
> 
>     3. evaluate the code using the eeval function defined in interpreter.rkt.
> 
> 
> 
> However, this returns an error "; mcdr: contract violation". I suspect that 
> the problem is in interpreter-self-evaluate.rkt and that it might have 
> something to do with how quote works. I might be completely off base though. 
> Any ideas?
> 
> 
> 
> --
> 
> You received this message because you are subscribed to the Google Groups 
> "Racket Users" group.
> 
> To unsubscribe from this group and stop receiving emails from it, send an 
> email to racket-users...@googlegroups.com.
> 
> For more options, visit https://groups.google.com/d/optout.
> 
> 
> 
> 
> 
> -- 
> 
> -- 
> Jens Axel Søgaard

I am somewhat reluctant to use structures as I want to keep the interpreter as 
minimal as possible. Also, I'm not familiar enough with the semantics of frames 
to implement it in interpreter.rkt.

With regards to mcons being different from cons, Oscar Lopez has suggested that 
in stackoverflow. So, I re-implemented the interpreter in r5rs so that set-car! 
and set-cdr! are available and I wouldn't need to use mcons. I've attached the 
files here.

I still got an error
; application: not a procedure;
;  expected a procedure that can be applied to arguments
;   given: (mcons 'expr (mcons 'env))
;   arguments...: [none]

It looks like it still has something to do with mcons. I suspect that this 
might have something to do with Racket's implementation of r5rs? Again, this 
might be completely wrong but I don't know how to determine the cause.

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interpreter-r5rs.rkt
Description: Binary data


interpreter-r5rs-self-evaluate.rkt
Description: Binary data

[racket-users] Self evaluating Racket Interpreter

[circularballs]

I posted this question on stackoverflow but have not found an answer yet. 
https://stackoverflow.com/questions/43476080/self-evaluting-racket-interpreter

I've been trying to write a Racket interpreter that can interpret itself. 

interpreter.rkt contains the code for the interpreter. It is pretty standard. 
Then, in interpreter-self-evaluate.rkt, I 
1. import interpreter.rkt, 
2. copy paste the code from interpreter.rkt and 
3. evaluate the code using the eeval function defined in interpreter.rkt.

However, this returns an error "; mcdr: contract violation". I suspect that the 
problem is in interpreter-self-evaluate.rkt and that it might have something to 
do with how quote works. I might be completely off base though. Any ideas?

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interpreter.rkt
Description: Binary data


interpreter-self-evaluate.rkt
Description: Binary data