[MLton-user] OP longvid not accepted

[Matthew Fluet]

On Mon, 21 Jan 2008, Vesa Karvonen wrote:
> On Jan 21, 2008 6:01 PM, Florian Weimer <fweimer at bfk.de> wrote:
>> I suppose the following program is valid according to the definition
>> (MLkit accepts it):
>>
>> val foo = op String.<

PolyML and HaMLet also accept it.  SML/NJ does not.  (MLton's SML .grm is 
a heavily modified version of SML/NJ's.)

> Yes, this would seem to be valid according to the grammar on page 10,
> which includes
>
>  atexp ::= <op> longvid

Yup, definitely allowed by the grammar.  Since a longvid can't be used 
infix, it isn't surprising that this generality in the grammar production 
is seldom used.

>> However, MLton requires that "op" is always followed by a plain VId,
>> not a longVId.
>
> That would seem to be the case.  Also, the same would seem to apply to patterns.

Yes.  MLton properly handles "<op> longvid" in the exbind production.