ODataV4 CBS $select question

question.txt

start UPDATE 30SEP2018:
In a comment on https://www.linkedin.com/feed/update/urn:li:activity:6449917998194008064
Dennis Ramondt (CBS Open Data) answers that the full $select functionality will be implemented only later
end UPDATE 30SEP2018

Support for $select in beta version CBS OData4

$select is not mentioned in the implementation document https://beta.opendata.cbs.nl/OData4/implement.html. 
When using the construct on three different subtables of 900001NED it behaves differently as shown below.
Here I use R code but I get the same results when I use the urls in an internet browser.

Question: is this the intended behaviour?

In the remainder of the file: effect on TypegebruikCodes, MeasureCodes, Observations (and Observation without $select)

Works fine for TypegebruikCodes
tc1 =HOQCutil::get_table_cbs_odata4_GET(
    "https://beta.opendata.cbs.nl/OData4/CBS-Maatwerk/900001NED/TypegebruikCodes?$select=Identifier,Title"
    ,response=T
)
HOQCutil::hard_split(httr::content(tc1,as='text'),80)
## [1] "{\"@odata.context\":\"https://beta.opendata.cbs.nl/OData4/CBS-Maatwerk/900001NED/$m"       
## [2] "etadata#TypegebruikCodes(Identifier,Title)\",\"value\":[{\"Identifier\":\"A045558\",\"Ti"  
## [3] "tle\":\"Energielevering; particuliere woning\"},{\"Identifier\":\"A045559\",\"Title\":\"En"
## [4] "ergielevering; zakelijke aansluiting\"}]}"


Gives an error for MeasureCodes
Apparently the result is an incomplete JSON expression. 
The browser message is SyntaxError: JSON.parse: unexpected end of data at line 1 column 130 of the JSON data.

mc1 =HOQCutil::get_table_cbs_odata4_GET(
    "https://beta.opendata.cbs.nl/OData4/CBS-Maatwerk/900001NED/MeasureCodes?$select=Identifier,Title"
    ,response=T
)
HOQCutil::hard_split(httr::content(mc1,as='text'),80)
## [1] "{\"@odata.context\":\"https://beta.opendata.cbs.nl/OData4/CBS-Maatwerk/900001NED/$m"
## [2] "etadata#MeasureCodes(Identifier,Title)\",\"value\":["


Gives an exception for Observations
obs1 =HOQCutil::get_table_cbs_odata4_GET(
  "https://beta.opendata.cbs.nl/OData4/CBS-Maatwerk/900001NED/Observations?$top=2&$select=Measure,Value"
    ,response=T
)
HOQCutil::hard_split(httr::content(obs1,as='text'),80)
## [1] "Error: Exception has been thrown by the target of an invocation."


Works fine for Observations without the $select
obs1 =HOQCutil::get_table_cbs_odata4_GET(
  "https://beta.opendata.cbs.nl/OData4/CBS-Maatwerk/900001NED/Observations?$top=2"
    ,response=T
)
HOQCutil::hard_split(httr::content(obs1,as='text'),80)
## [1] "{\"@odata.context\":\"https://beta.opendata.cbs.nl/OData4/CBS-Maatwerk/900001NED/$m"           
## [2] "etadata#Observations\",\"value\":[{\"Id\":1,\"Measure\":\"M00000001\",\"ValueAttribute\":\"N"  
## [3] "one\",\"Value\":2060.0,\"PostCode6\":\"1011AC\",\"Typegebruik\":\"A045558\"},{\"Id\":2,\"Measu"
## [4] "re\":\"M00000001\",\"ValueAttribute\":\"None\",\"Value\":850.0,\"PostCode6\":\"1011AH\",\"Type"
## [5] "gebruik\":\"A045558\"}]}"