JavaScript : Create a function that invokes the provided function with its arguments transformed

JavaScript fundamental (ES6 Syntax): Exercise-172 with Solution

Function with Transformed Arguments

Write a JavaScript program to create a function that invokes the provided function with its arguments transformed.

• Use Array.prototype.map() to apply transforms to args in combination with the spread operator (...) to pass the transformed arguments to fn.

Sample Solution:

JavaScript Code:

// Define a function 'overArgs' that takes a function 'fn' and an array of transformation functions 'transforms'
const overArgs = (fn, transforms) => 
  // Return a new function that takes any number of arguments
  (...args) => 
    // Apply the original function 'fn' to the arguments after applying the corresponding transformation functions
    fn(
      // Map over the arguments and transform each one using the corresponding transformation function
      ...args.map((val, i) => transforms[i](val))
    );
// Define a function 'square' that returns the square of its input
const square = n => n * n;
// Define a function 'double' that returns the double of its input
const double = n => n * 2;
// Define a new function 'fn' that takes two arguments and applies 'square' to the first argument and 'double' to the second
const fn = overArgs((x, y) => [x, y], [square, double]);
// Call 'fn' with two sample arguments and log the result
console.log(fn(9, 3)); // [81, 6]
console.log(fn(5, 2)); // [25, 4]

Output:

[81,6]
[25,4]

Visual Presentation:

Flowchart:

Live Demo:

See the Pen javascript-basic-exercise-172-1 by w3resource (@w3resource) on CodePen.

For more Practice: Solve these Related Problems:

• Write a JavaScript program that creates a function which applies a transformation to each of its arguments before invoking another function.
• Write a JavaScript function that maps input arguments using a callback and then passes them to the target function.
• Write a JavaScript program that demonstrates argument transformation by converting all inputs to strings before processing.
• Write a JavaScript function that accepts a transformation function and returns a new function that modifies its arguments accordingly.

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