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Re: [Scheme-reports] Possible error in latest available draft of R7RS

Hi Thorben,

On Wed, Feb 25, 2015 at 10:52 PM, Thorben Hasenpusch <t.hasenpusch@x> wrote:
Hello all!

While looking over the formal semantics paragraph of the latest draft of R7RS,
I might have spotted at least 2 possible bugs.

1. In the definition of the auxiliary function ‘cons’:
The anonymous function passed to ‘twoarg’ has its parameters ‘k’ and ‘w’ switched;
As it currently stands, the form of the function being passed to twoarg is E -> E -> K -> P -> C,
however ‘twoarg’ takes a function of the form E -> E -> P -> K -> C.

This and several other issues with the formal semantics were
pointed out by William Cushing.

I had let this slip my plate, but need to double check and all
these to the errata.

2. In the definition of ‘list’ and ‘tievalsrest’:
List is defined to take a parameter w ϵ P, however it never applies it to itself nor to ‘cons’, which also needs a parameter ϵ P.
Moreover, ‘tievalsrest’ uses ‘list’ in its definition, but doesn’t pass an argument ϵ P to it. In fact, it doesn’t even get a suitable parameter passed to.

William also pointed out the issue with `list', though missed that `tievalsrest' is calling list.

Thank you for the report!  I'll reply again when I've updated the errata.


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