dyna
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nwf
Are there any restrictions on return types?
This language looks amazing!
The tutorial leads me to believe the arguments to a functor must be strings or integers:
"We can also have rules which contain both variables and atoms. (An atom is an argument
to a functor. Types of atoms include strings in quotes, like "Steve", and numbers,
like 903 or 3.14159. Variables don’t count as atoms, because they stand in place of atoms.)"
A very cursory glance at this paper leads me to believe that a Dyna functor's return type can be specified as any type, or left unrestricted.
Is that so?
(I apologize if I'm asking this question in the wrong place; if that's so, please let me know where to move it.)
An item can take on values of two general types primitive types (e.g., string, int, Boolean) as well as recursive "Terms types" (e.g., x = &f(&g(&h(1))), lists [1,2 ,"a", ["b"] ]).
The unary operator &, known as "quote" is used to create these Term structures. To avoid clutter, functors can declare their default "disposition" via pragma directives. An example of such a functor is cons -- the list constructor` - it does not require explicit quoting because it's default disposition is "quoted".
So it sounds like anything I could represent in JSON, I could represent in Dyna?
Yes, JSON is a subset of what's representable in Dyna. At the moment, JSON is close fit for what's implemented in this language prototype since we don't yet support variable-variable unification (as in Prolog). Generally speaking, our types are (going to be) "tree automata with equality constraints".