presto-main/src/main/java/io/prestosql/sql/planner/optimizations/StreamPreferredProperties.java/StreamPreferredProperties/translateSymbols
class StreamPreferredProperties:    private static Optional<List<Symbol>> translateSymbols(Iterable<Symbol> partitioning, Function<Symbol, Optional<Symbol>> translator)
    {
        ImmutableList.Builder<Symbol> newPartitioningColumns = ImmutableList.builder();
        for (Symbol partitioningColumn : partitioning) {
            Optional<Symbol> translated = translator.apply(partitioningColumn);
            if (!translated.isPresent()) {
                return Optional.empty();
            }
            newPartitioningColumns.add(translated.get());
        }
        return Optional.of(newPartitioningColumns.build());
    }