[groovy2shoes]

Nice. I was under the impression that ALGOL's IF-THEN-ELSE statement was inspired by LISP (but I can't seem to find any references more reliable than some wikis). Also, if System F is going to get a line into Haskell, why not give the untyped lambda calculus a line into LISP?

I'm having trouble finding a detailed history of Clean, but I believe it predates Haskell. My understanding is that Miranda prompted a handful of lazy, pure functional languages. Haskell was an attempt to unify them. In Coders at Work, SPJ mentions that a few of those implementors were not interested in participating with the Haskell group. Is Clean one of those languages? (Of course, that doesn't mean they haven't influenced each other over the years, what I'm trying to suggest is that maybe an edge belongs from Miranda to Clean as well.)

It'd be interesting to see a graph of the influence of functional languages on other languages, too. Things like Python's list comprehensions borrowed from Haskell, and JavaScript borrowing lots of things from Scheme. I can only imagine that such a graph would be larger and less comprehensible than the present one!

[fogus]

All amazing questions -- you've managed to identify many gray areas of the graph. This graph is the seed to a large research project and will likely change as the research proceeds.

[kibwen]

What sort of research project? I'm also curious where you draw the line regarding "traditionally functional" languages with respect to multiparadigmatic languages.