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Jun 17, 2020 at 9:04 history edited CommunityBot
Commonmark migration
Apr 13, 2017 at 12:39 history edited CommunityBot
replaced http://codegolf.stackexchange.com/ with https://codegolf.stackexchange.com/
Feb 23, 2017 at 8:47 history edited Laikoni CC BY-SA 3.0
added fix function to become turing complete
Feb 21, 2017 at 15:03 comment added user62131 @Laikoni: There's no way to write an infinite loop in simply typed lambda calculus unless you have some extra help from something like a fixed-point combinator (the Y combinator is the best known but not the only one that exists); every combinator that would help you write an infinite loop doesn't exist in the type system in question. You can certainly do a lot of interesting things with terminating programs, but that isn't enough for Turing completeness.
Feb 21, 2017 at 15:01 comment added user62131 @PyRulez: If you have no lambdas and no other combinators, I don't think a fixed-point combinator like Y is enough by itself (although I'm very tired right now and there may well be something I'm missing).
Feb 21, 2017 at 12:33 comment added Christopher King @ais523 how many combinators does typed Lambda Calculus need to be complete? I think you just need the y combinator, right?
Feb 21, 2017 at 8:47 comment added Laikoni @ais523 The SKI combinators are just an example, using the given notation arbitrary lambda terms can be build, e.g. church numerals and functions on them.
Feb 21, 2017 at 8:37 comment added Laikoni @PyRulez As per the default rules I assumed that functions are acceptable.
Feb 21, 2017 at 2:34 comment added user62131 The simply typed SKI combinator calculus isn't Turing-complete; you need an untyped lambda calculus for that. Unfortunately, as your demonstrations mention, Haskell puts a typed interpretation on the code by default.
Feb 21, 2017 at 0:38 comment added Christopher King Won't it technically be removed at compile time without main?
Feb 21, 2017 at 0:18 history edited user61980 CC BY-SA 3.0
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Feb 20, 2017 at 19:28 history edited Laikoni CC BY-SA 3.0
added 290 characters in body
Feb 20, 2017 at 19:19 history answered Laikoni CC BY-SA 3.0