NYC LOCAL: Tuesday 12 March 2013 Lisp NYC: Arthur Smyles on Haskell Data Types in Scheme

[secr...@lxny.org]

<blockquote
what="almost official Lisp NYC announcement,
made by me from material at
http://lispnyc.org
and
http://www.meetup.com/LispNYC/events/78022182/"

more="http://www.schemers.org/Documents/Standards/R5RS/
http://mitpress.mit.edu/sicp/full-text/book/book.html
http://sicpebook.wordpress.com/ebook/

http://en.wikipedia.org/wiki/Haskell_%28programming_language%29
[above page was last modified on 8 March 2013 at 19:50]
http://en.wikipedia.org/wiki/Struct_%28C_programming_language%29
[above page was last modified on 28 February 2013 at 22:59]
http://en.wikipedia.org/wiki/Algebraic_data_type
[above page was last modified on 26 February 2013 at 02:58]

http://www.cse.unsw.edu.au/~zhangw/files/canonicalform.pdf
[above from 2004,
gives canonical forms for rooted unordered labelled trees,
claimed to be useful for sorting and searching such]

http://www.datomic.com/
[above is a system for dealing with, ah, this is embarrassing,
'semi-structured data', which here are almost really
just sexps, with special attention paid to 'time';
Rich Hickey is the author; there is a free version at
http://downloads.datomic.com/free.html
in addition there are at least two versions on Github,
and here is something made of Git and Datomic:
http://blog.datomic.com/2012/10/codeq.html]"

and-more="Actual code for a fancy type system, near to the minimal usual
implicit type system most mathematicians use:
http://math.andrej.com/2012/11/08/how-to-implement-dependent-type-theory-i/
http://math.andrej.com/2012/11/11/how-to-implement-dependent-type-theory-ii/
http://math.andrej.com/2012/11/29/how-to-implement-dependent-type-theory-iii/"

arithmetic-of-types="And algebra and calculus of types:
http://chris-taylor.github.com/blog/2013/02/10/the-algebra-of-algebraic-data-types/
http://chris-taylor.github.com/blog/2013/02/11/the-algebra-of-algebraic-data-types-part-ii/
http://chris-taylor.github.com/blog/2013/02/13/the-algebra-of-algebraic-data-types-part-iii/"

groebner-theorem="Has not been proved for types,
but a one dimensional Nullstellensatz
has been for some not useless type systems;
Example of a polynomial lying in an ideal:
http://blog.sigfpe.com/2007/09/arboreal-isomorphisms-from-nuclear.html
One dimensional Nullstellensatz:
http://arxiv.org/abs/math/0212377v1
[name of above paper:
Objects of Categories as Complex Numbers
by Marcelo Fiore, Tom Leinster]"

personal="The types themselves of ML and Haskell are
not difficult to understand. The type estimators
and type checkers are hard to understand,
because in their operation they are not explicit enough,
and I think few ML/Haskell hackers use the stepper
for the type estimator/checker. But the most difficult
thing, at least for Haskell, is the off putting miasma compounded
of grandiose claims and ridiculously imprecise statements in much
of the propaganda."
more-personal="I believe the fundamental claims of the propaganda.">


Haskell Data Types in Scheme by Arthur Smyles

Tuesday, March 12, 2013

7:00 PM

Meetup HQ, 9th Floor

632 Broadway, New York, NY


"The ultimate mashup of 2 great languages."

This talk demonstrates how to build your own data type
library resulting in a simple/functional/extensible record
system.

Similar to the way Haskell handles data types, included are:
value constructors, pattern matching, sum types, recursive
types and some thoughts on building type classes ...all in
Scheme!

</blockquote>


Distributed poC TINC:

Jay Sulzberger <secr...@lxny.org>
Corresponding Secretary LXNY
LXNY is New York's Free Computing Organization.
http://www.lxny.org