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Clojure, a Lisp type of language, has a so called Thread macro which converts nested function calls into a linear flow of function calls, thus improving readability, testability and inviting pure functional (reactive) programming.

I suppose that an equivalent in Mathematica would work as follows:

Let

 listany = {{1, 2}, {3, 4}}; 
 listopr = {Flatten, Map[f], Map[g]}; 

and assume that t is the equivalent of Clojure's -> ( thread macro ), and $f$ and $g$ are functions transforming elements of listany. Then:

 t[listany, listopr] 

would be translated to

 Map[g]@Map[f]@Flatten@listany

Similarly,

 t[5, {f, g, h}]

would be translated to

 h@g@f@5

Do you have a suggestion on how to implement t in Mathematica?

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    $\begingroup$ Look at Composition or RightComposition $\endgroup$
    – Carl Woll
    Feb 16, 2017 at 18:52
  • $\begingroup$ I knew it had to be somewhere in Mma. Suppose this works. $\endgroup$ Feb 16, 2017 at 19:16
  • $\begingroup$ @niloderoock Would you consider penning a self-answer, perhaps exploring the use of those two newly discovered functions? $\endgroup$
    – MarcoB
    Feb 16, 2017 at 21:05
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    $\begingroup$ Be careful with Composition: try x = 1; SymbolName@Unevaluated@x vs Composition[SymbolName, Unevaluated][x] more in closely related: 54762 $\endgroup$
    – Kuba
    Feb 16, 2017 at 21:14

1 Answer 1

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Inefficiently your operation is performed by ComposeList:

ComposeList[listopr, listany] // Last
{g[f[1]], g[f[2]], g[f[3]], g[f[4]]}

Composition

(Composition @@ Reverse @ listopr) @ listany

New-in-v10 RightComposition

(RightComposition @@ listopr) @ listany

The deprecated but reliable function Compose can also be applied with work:

Compose @@ Append[Reverse @ listopr, listany]

As Kuba comments these forms do not evaluate in the same way as the literal form. If you wish to create the complete expression before evaluation consider comp from my self-answer to:

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