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Re: eval'ing a self-referential vector


Jim Blandy <jimb@red-bean.com> writes:

> Here's R5RS's position on this issue:
> - The argument to Eval must be a valid expression represented as
>   Scheme data, and therefore must not be cyclic.  (6.5)
> - "It is an error for an operation to be presented with an argument
>   that it is not specified to handle." (1.3.3)
> - "An error situation that implementations are not required to detect
>   is usually referred to simply as `an error.'" (1.3.2)
> 
> So we don't have to catch it.

A vector is a valid expression even if it is cyclic.

It is well-specified how to handle it: a vector is self-evaluating.

So, I'd say that we have to be able to handle it.

/mdj