Talk:Partial function application: Difference between revisions
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(→What is partial application?: new section) |
(→Is Scala correct?: Yes, you can pass arity 3 function to map.) |
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: I've never written any Scala code and only seen a few samples, but this does look like partial application to me (quite similar to Perl 6's Whatever-Star). The fact that you have to mention a type signature might just be a limitation of Scala's type inferencer. The key question is: can you use this to pass an arity 3 function to map without using any intermediate definitions or lambda's? —''[[User:Ruud Koot|Ruud]]'' 07:05, 21 April 2011 (UTC) |
: I've never written any Scala code and only seen a few samples, but this does look like partial application to me (quite similar to Perl 6's Whatever-Star). The fact that you have to mention a type signature might just be a limitation of Scala's type inferencer. The key question is: can you use this to pass an arity 3 function to map without using any intermediate definitions or lambda's? —''[[User:Ruud Koot|Ruud]]'' 07:05, 21 April 2011 (UTC) |
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:: <lang scala>scala> def f(a: Int, x: Int, b: Int) = a * x + b |
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f: (a: Int,x: Int,b: Int)Int |
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scala> List(1, 2, 3).map(f(10, _, 1)) |
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res4: List[Int] = List(11, 21, 31)</lang> |
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:: Yes, you can pass arity 3 function to map. The _ has no type signature. A _ without a type signature can be an error, so I am not sure why it worked here. (I am new to Scala, and not the author of the Scala solution.) --[[User:Kernigh|Kernigh]] 19:00, 21 April 2011 (UTC) |
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==Is Lisp correct?== |
==Is Lisp correct?== |
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