JavaScript: Decapitalize the first letter of a string

JavaScript fundamental (ES6 Syntax): Exercise-24 with Solution

Decapitalize First Letter of String

Write a JavaScript program to decapitalize the first letter of a string.

• Use array destructuring and String.prototype.toLowerCase() to decapitalize first letter, ...rest to get array of characters after first letter and then Array.prototype.join('') to make it a string again.
• Omit the upperRest argument to keep the rest of the string intact, or set it to true to convert to uppercase.

Sample Solution:

JavaScript Code:

//#Source https://bit.ly/2neWfJ2 
// Define a function called `decapitalize` that converts the first character of a string to lowercase and optionally converts the rest of the string to uppercase.
const decapitalize = ([first, ...rest], upperRest = false) =>
  first.toLowerCase() + (upperRest ? rest.join('').toUpperCase() : rest.join(''));

// Example usage
console.log(decapitalize('W3resource'));  
console.log(decapitalize('Red', true));  

Note: Omit the upperRest parameter to keep the rest of the string intact, or set it to true to convert to uppercase

Output:

w3resource
rED

Visual Presentation:

Flowchart:

Live Demo:

See the Pen javascript-basic-exercise-1-24 by w3resource (@w3resource) on CodePen.

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