JavaScript: Accepts a converging function and a list of branching functions

JavaScript fundamental (ES6 Syntax): Exercise-68 with Solution

Converge Function with Branching Functions

Write a JavaScript program that accepts a converging function and a list of branching functions. It returns a function that applies each branching function to the arguments. The results of the branching functions are passed as arguments to the converging function.

• Use Array.prototype.map() and Function.prototype.apply() to apply each function to the given arguments.
• Use the spread operator (...) to call converger with the results of all other functions.

Sample Solution:

JavaScript Code:

//#Source https://bit.ly/2neWfJ2
// Define a function 'converge' that takes a 'converger' function and an array of functions 'fns' as arguments and returns a new function.
const converge = (converger, fns) => (...args) => 
  converger(...fns.map(fn => fn.apply(null, args)));

// Define functions 'average' and 'sum'.
const average = converge((a, b) => a / b, [
  arr => arr.reduce((a, v) => a + v, 0),
  arr => arr.length
]);

// Example usage:
console.log(average([6, 7])); // Output: 6.5  
console.log(average([1, 2, 3, 4, 5, 6, 7])); // Output: 4  

Output:

6.5
4

Visual Presentation:

Flowchart:

Live Demo:

See the Pen javascript-basic-exercise-68-1 by w3resource (@w3resource) on CodePen.

For more Practice: Solve these Related Problems:

• Write a JavaScript program that accepts multiple branching functions and a converging function to merge their outputs.
• Write a JavaScript function that applies several functions to the same arguments and then passes all results to a final function.
• Write a JavaScript program that demonstrates convergent composition by processing inputs through parallel functions and combining their outputs.

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