Re: [Sml-implementers] Subject: Standard ML

[Peter S. <se...@di...>]

Andreas,

> OK, here you go. Don't be shocked: the list is quite exhaustive and
> contains a lot of pedantic stuff. There are very few "major" issues.

Thanks for the list.  I believe the scarcity of major issues testifies
to the amount of work and care that has gone into the Definition, and
also reflects much feedback from thoughtful users and implementors.

It would probably take five years to obtain similar quality in a
new-style definition for a new language, and another five-ten years
before implementations agree on the interpretation of the fine
points. 

Reason enough not to destroy what we have.

> During compiling this I also made a bunch of contrived test files to
> see how implementations cope with some of the more obscure details 

This is a very useful idea, and the results comforting ...

But, I don't understand why valrec.sml test case should raise Bind:

    val rec LESS = fn x => x    (* will raise Bind *)
    and NONE as SOME = fn x => x
    val SOME = 1;  

According to rule (26), and as stressed in the comment to that rule,
the identifier status may change in the recursive binding, so LESS,
NONE and SOME are value variables, and the example is no different
from this:

    val rec a = fn x => x    (* will raise Bind *)
    and b as c = fn x => x
    val c = 1;  

Peter
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