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zot / Leisure

Polyglot, document-based computing environment. Leisure is very much in flux, right now; please check the readme, below. For a taste of the new version, click the link below, but be warned that it only works in Chrome.
http://zot.github.io/Leisure/?load=elisp/README.org
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Overhaul setType/getType #36

Closed zot closed 12 years ago

zot commented 12 years ago

Change setType and getType to use JS prototypes, with Function as the root -- metadata can be stored in prototype

zot commented 12 years ago

Maybe have optional type assertions (x :? person) for type checking, as opposed to dispatching. On an error, it could inspect the stack for violated assertions on items that have already been evaluated. Maybe there's a more transparent implementation of memoization, or a better way to tie it into the context stack?

zot commented 12 years ago

for f a b::tx c d::ty = code: generate a definition for f a b that returns b.f(a, b)->(c)->(d)->dispatcher code

Dispatch code works like a dispatch method in Xtend and dispatches based on d's type. The final method called can be named using the types in the secondary constraints, like f_ty().

Example: The Leisure code classify p::person s::shoe = concat[ 'Person: ' p ', shoe: ' s]

can (roughly) generate this _classify() method in the Leisure_person class:

Leisure_person._classify = (_p, _s)->
  if _s() instanceof Leisure_shoe then @_classify$Z_shoe(_p, _s)
  else if Leisure_Object._classify? then Leisure_Object._classify.apply(this, arguments)
  else throw new Error("No 'classify' function can handle a 2nd argument with type #{getType s}")

Leisure_person._classify$Z_shoe = (_p, _s)-> _concat()(->_cons()(->'Person')(_cons()(_p)(->_cons()(', shoe')(->_cons()(_s)(_nil)))))

The actual function body goes into Leisure_person._classify$Z_shoe. Further polymorphic definitions would generate other methods and rewrite the dispatch method, Leisure_person._classify(_p, _s)