Using F# in Visual Studio 2012, this code compiles:

let ``foo.bar`` = 5

But this code does not:

type ``foo.bar`` = class end

Invalid namespace, module, type or union case name

According to section 3.4 of the F# language specification:

Any sequence of characters that is enclosed in double-backtick marks (````),
excluding newlines, tabs, and double-backtick pairs themselves, is treated
as an identifier.

token ident =
    | ident-text
    | `` [^ '\n' '\r' '\t']+ | [^ '\n' '\r' '\t'] ``

Section 5 defines type as:

type := 
    ( type )
    type -> type       -- function type
    type * ... * type  -- tuple type
    typar              -- variable type
    long-ident         -- named type, such as int
    long-ident<types> -- named type, such as list<int>
    long-ident< >      -- named type, such as IEnumerable< >
    type long-ident    -- named type, such as int list
    type[ , ... , ]    -- array type
    type lazy          -- lazy type
    type typar-defns   -- type with constraints
    typar :> type      -- variable type with subtype constraint
    #type              -- anonymous type with subtype constraint

... and Section 4.2 defines long-ident as:

long-ident :=  ident '.' ... '.' ident

As far as I can tell from the spec, types are named with long-idents, and long-idents can be idents. Since idents support double-backtick-quoted punctuation, it therefore seems like types should too.

So am I misreading the spec? Or is this a compiler bug?

f# visual-studio-2012
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