presto-main/src/main/java/io/prestosql/metadata/FunctionRegistry.java/FunctionRegistry/toTypes
class FunctionRegistry:    private Optional<List<Type>> toTypes(List<TypeSignatureProvider> typeSignatureProviders)
    {
        ImmutableList.Builder<Type> resultBuilder = ImmutableList.builder();
        for (TypeSignatureProvider typeSignatureProvider : typeSignatureProviders) {
            if (typeSignatureProvider.hasDependency()) {
                return Optional.empty();
            }
            resultBuilder.add(metadata.getType(typeSignatureProvider.getTypeSignature()));
        }
        return Optional.of(resultBuilder.build());
    }