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| Date: | -- (:) |
| From: | Christian Stork <caml-list@c...> |
| Subject: | Camlp4 question on type declarations |
I'd like to construct a quotation that acts as the following pattern.
Ast.StTyp (_, (Ast.TyDcl (_, name, params, t, _)))
How can I do this? The obvious attempt
<:str_item< type $lid:name$ $list:params$ = $t$ >>
doesn't work because the 'list' antiquotation expander is not supported
(and AFAIU would be against the "spirit" of the overhault camlp4, altho
I wouldn't know why in this case).
There seem to be two problems. First, if one writes
<:str_item< type $lid:name$ $params$ = $t$ >>
(without the 'list:') then this pattern only matches a single parameter.
<:str_item< type $name_and_params$ = $t$ >>
doesn't work, even though one could think of name_and_params as a single
ctyp where name is applied to the params. (Wouldn't that be more
consistet with the modeling of type application in the rest of camlp4?)
Second problem: the above patterns only match type declarations without
any constraints. Something like
<:str_item< type $lid:name$ $param$ = $t$ $_$ >>
doesn't work either. (Admittedly, that would be hard to decypher
anyway.) The following only matches exactly one constraint.
<:str_item< type $lid:name$ $param$ = $t$ constraint $_$ = $_$ >>
Any solutions or do I have to fall back on using the underlying AST
constructors?
--
Chris Stork <> Support eff.org! <> http://www.ics.uci.edu/~cstork/
OpenPGP fingerprint: B08B 602C C806 C492 D069 021E 41F3 8C8D 50F9 CA2F