JavaScript: Create a function that accepts up to one argument, ignoring any additional arguments

JavaScript fundamental (ES6 Syntax): Exercise-115 with Solution

Single-Argument Function

Write a JavaScript program to create a function that accepts up to one argument, ignoring any additional arguments.

Note: Call the provided function, fn, with just the first argument given.

• Call the provided function, fn, with just the first argument supplied.

Sample Solution:

JavaScript Code:

//#Source https://bit.ly/2neWfJ2

// Define the 'unary' function.
const unary = fn => val => fn(val);

// Example usage: Applying parseInt as a unary function to each element of an array.
console.log(['6', '8', '10'].map(unary(parseInt)));
// Output: [6, 8, 10]

Output:

[6,8,10]

Flowchart:

Live Demo:

See the Pen javascript-basic-exercise-115-1 by w3resource (@w3resource) on CodePen.

For more Practice: Solve these Related Problems:

• Write a JavaScript program that creates a function which accepts at most one argument and ignores any additional ones.
• Write a JavaScript function that limits another function to only process its first argument regardless of how many are provided.
• Write a JavaScript program that wraps a multi-argument function so that it only uses the first parameter passed.

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