Uppercase the first character of each word in a string

JavaScript version
const uppercaseWords = (str) =>
str
.split(' ')
.map((w) => `${w.charAt(0).toUpperCase()}${w.slice(1)}`)
.join(' ');
// Or
const uppercaseWords = (str) => str.replace(/^(.)|\s+(.)/g, (c) => c.toUpperCase());
TypeScript version
const uppercaseWords = (str: string): string =>
str
.split(' ')
.map((w) => `${w.charAt(0).toUpperCase()}${w.slice(1)}`)
.join(' ');
// Or
const uppercaseWords = (str: string): string => str.replace(/^(.)|\s+(.)/g, (c) => c.toUpperCase());
Examples
uppercaseWords('hello world'); // 'Hello World'