tacit-programming

I've been using J for a few months now, and I find that reading unfamiliar code (e.g. that I didn't write myself) is one of the most challenging aspects of the language, particularly when it's in tacit. After a while, I came up with this strategy: 1) Copy the code segment into a word document 2) Take each operator from (1) and place it on a separate line, so that it reads vertically 3) Replace each operator with its verbal description in the Vocabulary page 4) Do a rough translation from J syntax into English grammar 5) Use the translation to identify conceptually related components and

Say I have a mean function defined like so: mean xs = sum xs / (fromIntegral $ length xs) but I want it in some tacit form, like this: mean = sum / (fromIntegral . length) Is there a built-in Haskell way to do something along these lines without having to build up my own tacit function (something like this): tacit :: (a -> b -> c) -> (d -> a) -> (d -> b) -> d -> c tacit a b c i = a (b i) (c i) In this form, the function looks like this: mean = tacit (/) sum (fromIntegral . length) but it feels like there might be a way to avoid having to use an explicit function such as this. I'm just

I'm currently learning the fascinating J programming language, but one thing I have not been able to figure out is how to filter a list. Suppose I have the arbitrary list 3 2 2 7 7 2 9 and I want to remove the 2s but leave everything else unchanged, i.e., my result would be 3 7 7 9 . How on earth do I do this? Yasir Arsanukaev The short answer 2 (~: # ]) 3 2 2 7 7 2 9 3 7 7 9 The long answer I have the answer for you, but before you should get familiar with some details. Here we go. Monads, dyads There are two types of verbs in J: monads and dyads . The former accept only one parameter, the