
To Dissect a Mockingbird: A Graphical Notation for the Lambda Calculus (1996) - louthy
http://dkeenan.com/Lambda/index.htm
======
tromp
My alternative graphical notation:

[http://www.cwi.nl/~tromp/cl/diagrams.html](http://www.cwi.nl/~tromp/cl/diagrams.html)

(also linked to at the bottom of the article)

Example: predecessor function on Church numerals:

    
    
      ┬──────────
      ┼─────┬────
      ┼─────┼─┬──
      │ ──┬─┼ ┼ ┬
      │ ┬─┼─┼ │ │
      │ │ ├─┘ │ │
      │ ├─┘   │ │
      └─┤     │ │
        └─────┤ │
              └─┘

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arethuza
Given this and the other relevant article on the front page about CSS I'm now
going to spend the rest of the day wondering if you can implement Starling and
Kestrel in CSS rather than getting work done.... :-)

[I know the answer is almost certainly "you can't" \- but I am intrigued as to
how close you can get]

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Sniffnoy
I'm going to repeat my comment from last time this came up-- this is a really
neat way of getting around the use of dummy variables, but why does he only
talk about beta reduction and never mention eta reduction? Describing eta
reduction in this notation is still easy.

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symmetricsaurus
I did like this. There is a certain elegance[1] to diagram based descriptions
of mathematical/physical concepts.

Another that is maybe more similar in that it removes a lot of dummy
variables(indices in this case) is the Penrose graphical notation[2] for
tensors. I have actually never calculated anything using these diagrams so I
don't know how practical they are.

[1]:[http://en.wikipedia.org/wiki/Feynman_diagram](http://en.wikipedia.org/wiki/Feynman_diagram)
[2]:[http://en.wikipedia.org/wiki/Penrose_graphical_notation](http://en.wikipedia.org/wiki/Penrose_graphical_notation)

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cscheid
Reminds me of the Bret Victor's "Alligator Eggs!":
[http://worrydream.com/AlligatorEggs/](http://worrydream.com/AlligatorEggs/)

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judk
The notation is interesting, but the "bird song "metaphor" makes me suspect
that this paper inspired the misguided era of monad metaphors that followed.

Birds, burritos, spacesuits ...

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peteretep
I read this a while ago, and have been telling people that Haskell's `id`
stands for `idiot` since then...

