presto-main/src/main/java/io/prestosql/metadata/ResolvedFunction.java/ResolvedFunction/fromQualifiedName
class ResolvedFunction:    public static Optional<ResolvedFunction> fromQualifiedName(QualifiedName name)
    {
        String data = name.getSuffix();
        if (!data.startsWith(PREFIX)) {
            return Optional.empty();
        }
        List<String> parts = Splitter.on(PREFIX).splitToList(data.subSequence(1, data.length()));
        checkArgument(parts.size() == 2, "Expected encoded resolved function to contain two parts: %s", name);
        Signature signature = decodeSimpleSignature(parts.get(0));
        FunctionId functionId = new FunctionId(parts.get(1));
        return Optional.of(new ResolvedFunction(signature, functionId));
    }