Re: [Caml-list] Error: The type abbreviation t is cyclic while defining submodules

[Gabriel Scherer <gabriel.scherer@gmail.com>]

> not in equations such as "with type t = t"
> which are a different construct, interpreted recursively

There is a typo above, I meant to say that such type constraints are
*not* recursive, and thus do not need a nonrec construction.

On Fri, Jun 10, 2016 at 4:05 PM, Gabriel Scherer
<gabriel.scherer@gmail.com> wrote:
> P.S.: Note that "nonrec" is only in definitions (struct .. end) and
> signatures (sig .. end), not in equations such as "with type t = t"
> which are a different construct, interpreted recursively -- not the
> best choice for consistency, but well.
>
> On Fri, Jun 10, 2016 at 4:03 PM, Gabriel Scherer
> <gabriel.scherer@gmail.com> wrote:
>> This is
>>
>>   type nonrec t = t
>>
>> which has been introduced in 4.02, after some years of internal usage
>> of (a syntax preprocessor implementing) it internally in Jane Street.
>>
>> On Fri, Jun 10, 2016 at 4:00 PM, Sébastien Hinderer
>> <Sebastien.Hinderer@inria.fr> wrote:
>>> Dear all,
>>>
>>> Assume the following code in a file points.ml:
>>>
>>> type t = float * float
>>>
>>> let compare = Pervasives.compare
>>>
>>> (* Other functions on points *)
>>>
>>> module OrderedPoints : Set.OrderedType with type t = t = struct
>>>   type t = t
>>>   let compare = compare
>>> end
>>>
>>> module PointSet : Set.S with type t = t = Set.Make(OrderedPoints)
>>>
>>>
>>> The line
>>>   type t = t
>>> yields the above mentionned error.
>>>
>>> Is there a way to let the compiler know that the t appearing after the
>>> "=" sign refers to the type defined at points.ml top level?
>>>
>>> Thanks!
>>>
>>> Sébastien.
>>>
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