nes.shift();
                    }
                    for (let line of lines) {
                        this.buffer.push(line);
                    }
                }

                nextLine() {
                    return this.buffer.shift();
                }
            }

            const runButton = document.getElementById("run");
            const replButton = document.getElementById("repl");
            const stopButton = document.getElementById("stop");
            const clearButton = document.g