CODEWITHSUNDEEP
javascriptfunctional-programming
Hasholef
Hasholef

Reputation: 753

How to implement pipe when the parent function receive different arguments

I'm new to functional programming and have a question regarding pipe.

Say I have the following function: 

const modifyArr = R.curry((i, newValue, arr) => 
                    Object.assign([], arr, {[i]: newValue}))

This function change an array's value on a specific index.

Now, I want to use this function twice (with pipe) in order to implement swap between two element in the array.

I cannot figured out how to write it. This is what I got:

const swap = (arr, a, b) => 
                R.pipe(modifyArr(b, arr[a], modifyArr(a, arr[b])))

Notice that the curried version of modifyArr (after receiving two arguments) expects an array, but I'm passing 3 arguments to the swap function.

How can I use pipe where my parent function receive a different arguments than the first function in the pipe?

Thanks.

Upvotes: 0

Views: 278

Answers (1)

Bergi
Bergi

Reputation: 665040

Given that your functions are curried, you can simply partially apply the former arguments before doing the piping:

const swap = (arr, a, b) => R.pipe(modifyArr(a, arr[b]), modifyArr(b, arr[a]))(arr);

Upvotes: 2

Related Questions