Version française
Home     About     Download     Resources     Contact us    

This site is updated infrequently. For up-to-date information, please visit the new OCaml website at

Browse thread
[Caml-list] Strange error message
[ Home ] [ Index: by date | by threads ]
[ Search: ]

[ Message by date: previous | next ] [ Message in thread: previous | next ] [ Thread: previous | next ]
Date: -- (:)
From: Jacques Garrigue <garrigue@k...>
Subject: Re: [Caml-list] Strange error message
From: Vitaly Lugovsky <>
> > In particular, I think that the question ``What means '_a ?''
> > from the
> > "EXPERT" FAQ could be relevant to your problem :)
>  No. Sorry. I still don't understand. Why there is a *wrong* type
> specification in .cmi? If it's '_a, why it's 'a in .cmi?

Did you read my answer?

What I believe is happening is that, the way you define it, execute
cannot be given a polymorphic type. This has become more confused
because you wrote a .mli.  Just erase the .mli (or get it out of the
way) and compile You should get a "this type variable is not
bound" error, which is what Pierre Weis is referring to.

Also note that '_a is only meaningful in output from the compiler.
If you write it in a .mli it will only be interpreted as a normal type
variable, in particular _it cannot match a non-generalizable one_
(only a closed type can).

Jacques Garrigue
To unsubscribe, mail Archives:
Bug reports: FAQ:
Beginner's list: