public string TryGetPreviouslyCompiledScript(string source)
{
//string key = source.Length.ToString() + source.GetHashCode().ToString();
string key = source.Length + Util.Md5Hash(source);
string assemblyName = "";
lock(PreviouslyCompiled)
PreviouslyCompiled.TryGetValue(key, out assemblyName);
//PreviouslyCompiled.TryGetValue (source, out assemblyName);
return assemblyName;
}