JSFiddle - React, Tailwind, and code Playground
by Daedalus
JavaScript
function ReplaceAt(input, search, replace, start) {
return input.slice(0, start)
+ input.slice(start).replace(search, replace)
+ input.slice(input.slice(0).length);
}
alert(ReplaceAt("my first my test", "my", "uuu", 9));