typewriter-effect.js

// typewriter effect

// After Effects script
// based on work of @MotionHub and @Wesley Wiyadi

// set this variables to configure
const blinkSpeed = 2;        // times per second
const speed = 15;            // how fast characters will appear
const startAt = 0;           // delay to start an effect
const cursorCharacter = '|'; // character to use as a cursor

const str = text.sourceText;    

const cursorVisible = Math.round(time*blinkSpeed) % 2;
const cursor =  cursorVisible ? ' ' : ;
const numCharacters = Math.floor(time * speed - startAt * speed);

numCharacters > 0 ? str.substr(0, numCharacters) + cursor : cursor;