pipe map operator

[maninalift]

I seem to specialize in reporting feature requests that I find interesting but even I am not entirely convinced by.

In this case it's the idea of vector pipes, AKA |> map. I like the idea of being able to represent this action with a single operator. :> fits because it looks like |> and : looks a bit like an array of little dots (cute).

When we want to pipe we will soon want to flatten so we can extend this syntax so that .> means |> concat-map and .:> means |> (concat-map . map) etcetera.

So that for example x .:..:> f means map f over the 5-deep array x, flattening the top three and bottom two levels together

e.g.

   x =
     * * * * <[a b c]>
           * <[d e f]>
         * * <[g h i]>
             <[j k l]>
       * * * <[m n o]>
         * * <[p q r]>
         * * <[s t u]>
     * * * * <[v w x]>
           * <[y z]>

   x .:..:> (.to-upper-case!)
 # = [["A","B","C","D","E","F","G","H","I","J","K","L"],["M","N","O","P","Q","R","S","T","U"],["V","W","X"],["Y","Z"]]

I don't think that there are that many places in people's code involving 5-deep arrays but the syntax pleases me so I thought I would suggest it.

Finally. You could add a | to make the syntax more robust to ambiguity: |:>, |.:>, and so on. With this addition it is easier to safely add more to the syntax such as mapping over objects without being too greedy with the syntax-space.

[vendethiel]

ref satyr/coco#187

[robotlolita]

Coco definitely seems to be on-par with Perl in terms of syntax.

What's wrong with flatten <| traverse (.to-upper-case!), xs? (Given an implementation of traverse as in http://hackage.haskell.org/package/base-4.6.0.1/docs/Data-Traversable.html)

[vendethiel]

One of coco's principle is "Perl over Ruby.", so it makes sense.
I agree there's no need for it, though

[vendethiel]

Remembered #319