sketch of tcp socket repl - modification of original udp repl-client.javascript

gistfile1.txt

// based on original udp repl-client.javascript
const net = require('net');
const readline = require('readline');

const client = new net.Socket();

const rl = readline.createInterface({
  input: process.stdin,
  output: process.stdout
});

const arcadiaPort = process.argv[2] || 5555;
// XXX: Unity Editor on Linuxen listens on tcp4 5555, so
//      127.0.0.1 is not a good idea there...
//const arcadiaHost = process.argv[3] || "127.0.0.1";
const arcadiaHost = process.argv[3] || "::1";

var input = "";

client.connect(arcadiaPort, arcadiaHost, () => {
  rl.on('line', (cmd) => {
    // always grow input
    input += cmd + "\n";
    if (parenthesesAreBalanced(input)) {
      // send balanced form to server
      client.write(input);
      // reset input
      input = "";
      // pause prompt until message event
      rl.pause();
    }
  });

  rl.on('close', () => {
    process.exit(0);
  });

  client.on('data', (data) => {
    var msg = data.toString();
    var msgLines = msg.split("\n");
    
    // set last line as prompt
    rl.setPrompt(msgLines.pop());
    // display all other lines
    console.log(msgLines.join("\n"));
    // result prompt
    rl.prompt();
  });

  client.on('ready', () => {
    // send header form to start prompt
    client.write('(binding [*warn-on-reflection* false] (do (println "; Arcadia REPL") (println (str "; Clojure " (clojure-version))) (println (str "; Unity " (UnityEditorInternal.InternalEditorUtility/GetFullUnityVersion))) (println (str "; Mono " (.Invoke (.GetMethod Mono.Runtime "GetDisplayName" (enum-or System.Reflection.BindingFlags/NonPublic System.Reflection.BindingFlags/Static)) nil nil)))))');
  });

});
    
// http://codereview.stackexchange.com/questions/45991/balanced-parentheses
function parenthesesAreBalanced(s) {
  var parentheses = "[]{}()",
      stack = [], // Parentheses stack
      i, // Index in the string
      c; // Character in the string

  for (i = 0; c = s[i++];) {
    var bracePosition = parentheses.indexOf(c),
        braceType;
    // ~ is truthy for any number but -1
    if (!~bracePosition) {
      continue;
    }

    braceType = bracePosition % 2 ? 'closed' : 'open';

    if (braceType === 'closed') {
      // If there is no open parenthese at all, return false OR
      // if the opening parenthese does not match ( they should be neighbours )
      if (!stack.length ||
          (parentheses.indexOf(stack.pop()) != bracePosition - 1)) {
        return false;
      }
    } else {
      stack.push(c);
    }
  }
  // If anything is left on the stack <- not balanced
  return !stack.length;
}