Re: Using eval with environments and R7RS modules

[Per Bothner <per@bothner.com>]

On 11/30/20 2:13 AM, Damien MATTEI wrote:
> (define (foo L)
> 
>     (eval L (interaction-environment))
> 
> and i got an error like UNBOUND VARIABLE L
> 
> but this not only in Kawa,it is in Scheme, i was in a R5RS ,

The eval functon is really not compatible with lexical scoping, at least
not unless you use a different evaluation strategy which make Scheme
run much slower and use more memory. And that would be all the time,
not just when eval is used (possibly unless you made eval a special
syntax the compiler could recognize, rather than a procedure).

Scheme from the very beginning has focused on lexical scoping and
being able to compile it to efficient code:

https://en.wikisource.org/wiki/Lambda_Papers

> if there is a way to know the current bindings from EVAL i will be happy

Dynamic bindings, yes, but lexical bindings, no.  And that won't change.

> to know it, because without this , i do not see any use for EVAL ,

I've many times said there is very little use for eval, and that too many
people overuse it.

If you think you have a good use for eval, you're probably wrong.

> having only the toplevel bindings is not enought for development.

If you mean that eval is not very useful for debugging, that is true.
-- 
	--Per Bothner
per@bothner.com   http://per.bothner.com/