[Haskell-cafe] Re: grammars and generics

Chung-chieh Shan ccshan at post.harvard.edu
Tue Dec 11 16:02:29 EST 2007

Greg Meredith <lgreg.meredith at biosimilarity.com> wrote in article <5de3f5ca0712111100l79ec280fl1d828b12125abbdc at mail.gmail.com> in gmane.comp.lang.haskell.cafe:
> Here is an idea so obvious that someone else must have already thought of it
> and worked it all out. Consider the following grammar.


If I understand your basic idea correctly, it is to split a recursive
data type into two parts, a non-recursive type constructor and a
knot-tying recursive type.  This idea has been christened "two-level
types" by

    Tim Sheard and Emir Pasalic. 2004.  Two-level types and
    parameterized modules.  Journal of Functional Programming

The idea dates earlier, to initial-algebra semantics and "functional
programming with bananas and lenses":

    Mark P. Jones. 1995.  Functional programming with overloading and
    higher-order polymorphism.  In Advanced functional programming:
    1st international spring school on advanced functional programming
    techniques, ed. Johan Jeuring and Erik Meijer, 97-136.  Lecture
    Notes in Computer Science 925.

    Erik Meijer, Maarten Fokkinga, and Ross Paterson. 1991.  Functional
    programming with bananas, lenses, envelopes and barbed wire.  In
    Functional programming languages and computer architecture: 5th
    conference, ed. John Hughes, 124-144.  Lecture Notes in Computer
    Science 523.


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