camlp4 3.10: <:ctyp< ( $list:tys$ )

[Joel Reymont <joelr1@gmail.com>]

This is the old code:

     | <:ctyp< ( $list:tys$ ) >> -> tupl _loc (List.map aux tys)

I figure it tries to match something like "int * int".

Following Nicolas's suggestion I thought I would see what this  
expands to:

camlp4of -str '<:ctyp< ( int * int ) >>'
Ast.TyTup (_loc,
   Ast.TySta (_loc, Ast.TyId (_loc, Ast.IdLid (_loc, "int")),
     Ast.TyId (_loc, Ast.IdLid (_loc, "int"))))

How do I work back from this to the right expression within parens in  
the original pattern above? I tried

     | <:ctyp< ( $tup:tys$ ) >> -> tupl _loc (List.map aux tys)

but this produces ctyp instead of ctyp list so it's not suitable for  
the tupl.

	Thanks, Joel

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