Re: [Caml-list] Camlp4: generating printers of types

[Daniel de Rauglaudre <daniel.de_rauglaudre@inria.fr>]

Hi,

On Mon, Dec 09, 2002 at 06:01:41PM -0800, Ken Rose wrote:

> 1. Is there a clean way to handle (sum) types with constructors with
> multiple module qualifications?  I hacked the example to deal with
> Foo.bar, but it doesn't seem to extend automatically to Foo.Bar.baz.  As
> I understand it, I'd need a new pattern for each additional uid.

I don't understand that: in the type definition, there is no qualifications
for the constructors.

> 2. How are tuples represented in camlp4's syntax?  This is so I can
> match them when analyzing a type.

In Revised syntax, they are like in normal syntax, but the parentheses
are compulsory.

> 3. This is the big one.  When working on a type like:
> type t = int
> with the obvious extention to Daniel's code, the preprocessor produces
> type t = int let rec print_t = print_int
> Which the compiler rejects with "This kind of expression is not allowed
> as right-hand side of `let rec'"  I haven't been able to figure out a
> way to sneak it past, either.  What's going on here?  Why can't I rename
> print_int?

This message of OCaml just means that there are syntactic restrictions
of the "let rec". In this case, you should produce either a "let" without
"rec" or, an eta extension: "let rec print_t x = print_int x".

-- 
Daniel de RAUGLAUDRE
http://cristal.inria.fr/~ddr/
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