require("IRReceiver") - out of memory (eventually)

require("IRReceiver").connect(NodeMCU.D1, function(code) {
  console.log(code);
  if ( code.length >= 33 ) {
    var l=parseInt(code.slice(1,16),2);
    if ( l === 15344 ) {
        lcd.setCursor(0,1);
      var k=parseInt(code.slice(17,21),2);
      console.log({k:k,b:button[k]});
      lcd.clear();
      lcd.print(button[k]);
    }
  }
});

I have discovered at night a fluro lamp triggers the IR reciever. These random pulses after a couple of hours trigger this:

11111111111111111111111111111111111111111111111111111111111101111111111110111
11111111111111111110111111111111111111111110
1111111111111111111111111111111111111111111110111111111111111111101111
11111111111111111111111111111111011111111111
0111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111101111111111111111111111111111111111111110111111111111110111101111111111111111111111111111111111111111111111110111111111111111111111111111111111111111111111111111111
11111111111111111111110111011111111111111111111111111111111111111111110111111111111111111111111111110111111111111111111111111101111111111111111111110111111111111111111111111011111111111111111111111011111111111111111110111111111111111111111111111111111111111111111101010111111111111111111111111111111111111111111111110111011111111111111111111111111111111111101111111111111111111101101111111011111111111111111011111111111111111101111111111111111111111111111111111111111011111111111101011111111111111111111111
ERROR: Out of Memory!
ERROR: Ctrl-C while processing watch - removing it.
Execution Interrupted during event processing.
at line 1 col 40
...astTime;b&&(clearTimeout(b),b=void 0);.04<c?(""!==a&&e(a),a=...
                              ^
in function called from system
> 

it appears to be in this block:

 // set our callback to happen whenever pin goes low (eg, whenever pulse starts)
  setWatch(function(e) {
    var d = e.time-e.lastTime;
    if (timeout) {
      clearTimeout(timeout);
      timeout = undefined;
    }

I believe the cause is here:

    if (d>0.04) { // a gap between transmissions
      if (code!=="") callback(code);
      code = "";
    } else {
      code += 0|d>0.0008;

So code just keeps getting longer.... I wondering what the best way is to make this robust?

Set a watch dog timer that truncates the code string if it gets too long, or simply controls it's length?

http://www.espruino.com/modules/IRReceiver.js