presto-main/src/main/java/io/prestosql/operator/scalar/ArrayTransformFunction.java/ArrayTransformFunction/ArrayTransformFunction
class ArrayTransformFunction:    private ArrayTransformFunction()
    {
        super(new FunctionMetadata(
                new Signature(
                        "transform",
                        ImmutableList.of(typeVariable("T"), typeVariable("U")),
                        ImmutableList.of(),
                        arrayType(new TypeSignature("U")),
                        ImmutableList.of(
                                arrayType(new TypeSignature("T")),
                                functionType(new TypeSignature("T"), new TypeSignature("U"))),
                        false),
                false,
                ImmutableList.of(
                        new FunctionArgumentDefinition(false),
                        new FunctionArgumentDefinition(false)),
                false,
                false,
                "apply lambda to each element of the array",
                SCALAR));
    }