presto-main/src/main/java/io/prestosql/operator/scalar/FormatFunction.java/FormatFunction/convertToString
class FormatFunction:    private static Object convertToString(MethodHandle handle, Object value)
    {
        try {
            return ((Slice) handle.invoke(value)).toStringUtf8();
        }
        catch (Throwable t) {
            throw internalError(t);
        }
    }