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e19293001

For those who want to grok lambda calculus, I would highly recommend "An Introduction to Functional Programming Through Lambda Calculus" book by Greg Michaelson[0]. After going through the book, I could say that you're brain will adapt the functional programming paradigm if you are used to the imperative programming language. Functional programming will change the way you think and make you a better programmer.

[0] - https://pdfs.semanticscholar.org/d986/546bc3780db3a3c0f8d88b...

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I was lucky enough to be taught lambda calculus and related topics at Heriot-Watt by Greg - I'll never forget the moment when he introduced the S and K combinators - been fascinated with those ever since.

[NB Related topics included strongly recommending GEB].

> I'll never forget the moment when he introduced the S and K combinators - been fascinated with those ever since.

Rabbit hole warning. If you go down this particular hole you will lose at least a month and maybe more. It will be the most fun you've had in a long time but your productivity will take an extreme hit.

Indeed, my final year project was to build a functional programming language that macro expanded into lambda calculus the transform that into different sets of combinators and look at the performance improvements.

To this day (almost exactly 30 years) - I am staggered that you can express Y in terms of S & K. I know this follows trivially but actually having coded it and watched it run (slowly) did made it very real to me.

NB This was running on an Orion minicomputer with rather limited memory - I had to implement a mark and sweep garbage collector to get expressions of any size to run!

Do you still have this? That would be a very nice project to share.

I still have a print out of it - I did find myself considering the idea of re-implementing it in something a bit nicer than 1980s K&R C.

I'd be happy to help if you want.

It's somewhere on my long list of projects to work on - thanks for the offer though :-)

Seconded--I got this book on a whim and didn't expect to finish it very quickly, but I was having so much fun with it it displaced all the other books I was working on at the time. This was step two on my journey towards embracing FP (step one was seeing OCaml in a class).

It's intended more for kids, but Alligator Eggs is a fun way to play with lambda calculus: http://worrydream.com/AlligatorEggs/

Sounds very promising!

To make sure(er) the PDF sticks around, here it is stored on IPFS: https://ipfs.io/ipfs/QmRKHcRYBpYJBWbiRkPeGA9kWfsjUtZPq45oMi6...

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