docs: private static void setScriptVarImpl(String scriptName, String key, String value) {	
  		validateKey(key);
  		
  		Map<String, String> scVars = scriptVars
  				.computeIfAbsent(scriptName, k -> Collections.synchronizedMap(new HashMap<String, String>()));
  		
  		if (value == null) {
  			scVars.remove(key);
  		} else {
  			validateValueLength(value);
  			if (scVars.size() > MAX_SCRIPT_VARS) {
  				throw new IllegalArgumentException("Maximum number of script variables reached: " + MAX_SCRIPT_VARS);
  			}
  			scVars.put(key, value);
  		}
  	}