a container used by RLink to represent any R environment.
- Only the global R environment is fully supported. All other R environments are still represented by , but the specific information about them is lost. Therefore, R objects whose Wolfram Language representation contains references to non-global R environments cannot generally be correctly exported back to R.
- Like RCode, is a head providing representation rather than equivalence. Exporting to R objects previously imported to the Wolfram Language (or their parts) containing any of these heads is not guaranteed to produce equivalent objects in the R workspace.
- Expressions with the head transform trivially (are left unchanged) by the functions ToRForm and FromRForm.