text: const readline = require('readline');
  
  exports.$addEventListener = (elId, event, callback) => {
  	document.getElementById(elId).addEventListener(event, callback);
  };
  exports.$onClick = (elId, callback) => {
  	this.$addEventListener(elId, 'click', callback);
  };
  
  const outputLogMessage = (message, lineClass) => {
  	let p = document.createElement('p');
  	p.classList.add(lineClass);
  	p.innerText = message;
  	return p;
  };
  exports.outputLogMessage = outputLogMessage;
  
  exports.outputReadLine = (stream, lineClass, elOutput) => {
  	readline.createInterface({
  		input     : stream,
  		terminal  : false
  	}).on('line', line => {
  		elOutput.appendChild(outputLogMessage(line, lineClass));
  	});
  };
  
  exports.findButtonicon = (el) => {
  	return el.childNodes[1];
  };
  