presto-main/src/main/java/io/prestosql/operator/scalar/MapZipWithFunction.java/MapZipWithFunction/MapZipWithFunction
class MapZipWithFunction:    private MapZipWithFunction()
    {
        super(new FunctionMetadata(
                new Signature(
                        "map_zip_with",
                        ImmutableList.of(typeVariable("K"), typeVariable("V1"), typeVariable("V2"), typeVariable("V3")),
                        ImmutableList.of(),
                        mapType(new TypeSignature("K"), new TypeSignature("V3")),
                        ImmutableList.of(
                                mapType(new TypeSignature("K"), new TypeSignature("V1")),
                                mapType(new TypeSignature("K"), new TypeSignature("V2")),
                                functionType(new TypeSignature("K"), new TypeSignature("V1"), new TypeSignature("V2"), new TypeSignature("V3"))),
                        false),
                false,
                ImmutableList.of(
                        new FunctionArgumentDefinition(false),
                        new FunctionArgumentDefinition(false),
                        new FunctionArgumentDefinition(false)),
                false,
                false,
                "merge two maps into a single map by applying the lambda function to the pair of values with the same key",
                SCALAR));
    }