Talk:Catamorphism

From Rosetta Code

Name change?[edit]

To "Reduce"? --Paddy3118 (talk) 01:46, 11 August 2013 (UTC)

Clarity needed[edit]

Is it a left fold or right fold? Is the applied function left- or right-associative? –14:15, 18 September 2012 (UTC)

It also needs instructions on what to do. A task by definition is something to do. This is just an informational page about what "reduce" means. --Mwn3d 15:55, 18 September 2012 (UTC)
I just wanted to see the various reduce methods from other languages. I put it in as a draft, should I have made it in a sandbox instead? Kzh 15:59, 18 September 2012 (UTC)
I added to the task description. Hope it's OK Kzh. --Paddy3118 16:16, 18 September 2012 (UTC)
Drafts are absolutely fine, but it's considered polite to do at least one implementation with your task suggestion to get things started. It also helps us clarify the draft, working out which parts of the suggestion are essential and which are just features of the implementation you had in mind. (It's also possible to go straight to a full task, but that takes a bit of practice at task writing so that you can write an abstract description of something generally implementable and interesting/relevant. But the way to get practice is to practice of course! Doing copy-editing of a language's RC example set can help too, especially if it's got a lot of implementations of tasks already. But I'm digressing…) –Donal Fellows 23:02, 18 September 2012 (UTC)

I still think that it is not specific enough. It doesn't give a specific task of what to fold. The examples just demonstrate the folding of a few arbitrary operators, which are not consistent between examples. Also, many of the things that are folded in the examples are commutative, so they cannot be used to demonstrate the difference between left and right fold. --Spoon! 01:51, 30 September 2012 (UTC)