/// <summary>
/// Gets a previously declared function by name and number of parameters.
/// </summary>
private ScriptMemberFunction getFunction(string name, int paramCount)
{
    ScriptMemberFunction result = null;

    foreach (ScriptMemberFunction func in declaredFunctions)
    {
        if (name == func.FunctionName)
        {
            // AutoIt does not do function overloading
            if (paramCount >= func.MinParams && paramCount <= func.MaxParams)
            {
                result = func;
            }
            else
            {
                throw new AutoItException("Incorrect number of parameters in function call");
            }
        }
    }
    if (result == null)
    {
        throw new AutoItException("Unknown function name.");
    }
    return result;
}