Unscrew list literal syntax in VentureScript

[axch]

From a venstan example:

quote("y_out"("y", "UArray(Number)", "N")())

is how one spells what in the abstract syntax looks like

'(("y_out" "y" "UArray(Number)" "N"))

This is because the VentureScript syntax for lists of all kinds is <first_elt>(<second-elt>, <third-elt>, ...) regardless of whether they are meant as function application syntax or as list literals.

The same problem screws attempts to use the cond and letrec macros.

[axch]

The Scheme community has put some (not very broadly adopted) thought into surface syntaxes that would be both "more traditional" yet still homoiconic. See

• http://srfi.schemers.org/srfi-119/srfi-119.html
• http://srfi.schemers.org/srfi-110/srfi-110.html
• http://srfi.schemers.org/srfi-105/srfi-105.html
• http://srfi.schemers.org/srfi-49/srfi-49.html

for examples in Scheme proper. I also wouldn't be surprised if the Racketeers have something in this space.

[lenaqr]

Clojure suggests another option, which is that vectors with square brackets [a b c] evaluate as literal vectors, and many special forms use vectors instead of lists for internal grouping syntax (e.g. (let [var exp] body), (fn [arg] body)). Clojure's list/vector distinction is a little weird in that it conflates different data representations with different interpretations, and it would be a departure from Scheme style (as Venture is implemented so far), although a self-evaluating vector literal would be useful in its own right. (Maybe that should be a separate issue.)

[axch]

Workaround: One can always write

list(list("y_out", "y", "UArray(Number)", "N"))

That way there's extra verbiage, but at least the parens are all in reasonable places.

[axch]

We recently added syntactic sugar for array literals (with square brackets) (#511). That might be considered enough for this use case. The other reasonable thing to do would be to suppress leading subform motion under quote or quasiquote.