[plt-dev] #hash vs. #s

Thanks!

Now that I try your patch, though, I see a problem that I overlooked
before. In the syntax system, a hash table is not treated like pairs,
vectors, boxes, or prefabs, in that lexical information is not
propagated from the hash table to its content.

As a result, the example

  (let ([x 5]) `#hash(("coconut" . ,(+ 1 x))))

doesn't work.

I'll look into changing the syntax system to propagate information into
the values (and not the keys) of hash tables, and I'll save your
patches until that change is ready.

At Sun, 08 Feb 2009 14:08:44 -0500, Dave Herman wrote:
> Patch for collects/tests/mzscheme/syntax.ss attached.
> 
> Dave
> 
> Dave Herman wrote:
> > Attached is a patch for collects/scribblings/reference/syntax.scrbl that 
> > documents the quasiquote behavior. I'll create some new quasiquote tests 
> > and send a patch for that tomorrow.
> > 
> > Dave
> > 
> > 
> > On Feb 6, 2009, at 11:52 PM, Dave Herman wrote:
> > 
> >>> Oops --- I meant to vote for "1", not "2".
> >>>
> >>>> Doesn't that mean that some hash tables that should have literal
> >>>> representations won't?
> >>>
> >>> Yes, at least in terms of quasiquote. That's a good reason against 2.
> >>
> >> Okay, patch attached. Not sure if I did this right but hopefully it 
> >> helps.
> >>
> >> Dave
> >> <qq-and-or.patch>
> >> _________________________________________________
> >>  For list-related administrative tasks:
> >>  http://list.cs.brown.edu/mailman/listinfo/plt-dev
> > 
> 
> --- /home/dherman/Desktop/syntax.ss	2009-02-08 14:06:49.743750000 -0500
> +++ syntax.ss	2009-02-08 14:05:32.353125000 -0500
> @@ -651,6 +651,28 @@
>  (test '(quasiquote (quasiquote (quasiquote (unquote (unquote (unquote x)))))) 
> 'qq ````,,,x)
>  (test '(quasiquote (quasiquote (quasiquote (unquote (unquote (unquote 5)))))) 
> 'qq ````,,,,x)
>  
> +(test '#hash() 'qq `#hash())
> +(test '#hash(("apple" . 1) ("banana" . 2) ("coconut" . 3))
> +      'qq
> +      `#hash(("apple" . 1) ("banana" . 2) ("coconut" . 3)))
> +(test '#hash(("apple" . 1) ("banana" . 2) ("coconut" . 3))
> +      'qq
> +      `#hash(("apple" . ,1) ("banana" . ,(add1 1)) ("coconut" . ,(+ 1 2))))
> +(test '#hash(("foo" . (1 2 3 4 5)))
> +      'qq
> +      `#hash(("foo" . (1 2 ,(+ 1 2) 4 5))))
> +(test '#hash(("foo" . (1 2 3 4 5)))
> +      'qq
> +      `#hash(("foo" . (1 2 ,@(list 3 4 5)))))
> +(test '#hash((,(read) . 1) (,(+ 1 2) . 3))
> +      'qq
> +      `#hash((,(read) . 1) (,(+ 1 2) . ,(+ 1 2))))
> +(test '#hash((,(read) . 2))
> +      'qq
> +      `#hash((,(read) . 1) (,(read) . 2)))
> +(syntax-test #'`#hash(("foo" . ,@(list 1 2 3 4 5))))
> +(error-test #'(read (open-input-string "`#hash((foo ,@(list 1 2 3 4 5)))")) 
> exn:fail:read?)
> +
>  (test '(quasiquote (unquote result)) 'qq `(quasiquote ,result))
>  (test (list 'quasiquote car) 'qq `(,'quasiquote ,car))
>