You can clone with
At the moment the lexer supports some of the known tokens. It should be fairly trivial to add support for all the known tokens, particularly given that most keywords and operators are already presented in Tokens.xml.
Note: currently Tokens.xml is transformed by a tool that is not shipped with the SDK (issue in youtrack).
The requirement then would be to write tests (LexerTestBase could help here) to ensure that various F# constructs are correctly processed.
Excellent reference here http://blogs.msdn.com/b/dsyme/archive/2008/09/01/the-f-operators-and-basic-functions.aspx