u/oddasatin r/haskell • Recommends
Essentials: Functional Programming's Y Combinator - Computerphile
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#ycombinator#lambdacalculus#recursion
Essentials: Functional Programming's Y Combinator - Computerphile
Computerphile
2.6M subscribers • 70 videos on Hallway
- Recommended by 1 person: 1 in engineering communities.
- Presented by Graham Hutton, Professor at the University of Nottingham
Intermediate. Assumes working knowledge.
350K views9 years ago1 recommendation
Computer scienceProgramming languagesFunctional programmingComputation and complexity
Graham Hutton explains how to encode recursion in the lambda calculus using the Y combinator.
Encoding recursion in the Lambda calculus, one of Professor Graham Hutton's favourite functions. Lambda Calculus: youtu.be/eis11j_iGMs Professor Brailsford on 'Pointers': Coming Soon! Many thanks to Microsoft Research UK for their support with the 'Essentials' mini-series. facebook.com/computerphile twitter.com/computer_phile This video was filmed and edited by Sean Riley. Computer Science at the University of Nottingham: bit.ly/nottscomputer Computerphile is a sister project to Brady Haran's Numberphile. More at bradyharan.comWhy it's here
1 person recommends thisWhat people say. Recommended as an accessible explanation of the Y combinator and lambda calculus.
Moments people linked to
u/gazpacho_arabein r/haskell • Mentions
On “Monthly Hask Anything (April 2018)”
So i was watching this video on computerphile about the y combinator and the guy poses a question, using a function
rec f = f(rec(f))
define the factorial function like so
rec (\f.\n. <your code>) and (more by luck than judgement) i've got an answer that works, but I'm not sure its what the actual answer is. Its
fac = rec(\f n -> if (n == 1) then 1
else n * f(n-1))
But I'm unsure of exactly what is going on. I get that the lambda is the the argument provided to rec, but what exactly is the argument for \f? Is it rec itself, or maybe the lambda?
Is rec behaving like a higher order function that abstracts recursion in an arbitrary way? If s…
u/emptyflaskin r/compsci • Mentions
On “Programming in Lambda Calculus”
There's some good stuff on YouTube, like computerphile: link to this video