QPL license issue on toplevel

QPL license issue on toplevel

[Zheng Li]

Dear list,

I'm working towards a pure library version of the enhtop (an enhanced 
toplevel). I have some question about the toplevel's license of OCaml (QPL).

IMHO, OCaml toplevel allows to dynamic load libraries that are 
distributed *independently* under other licenses (even GPL or 
proprietary ones). I'm not sure about the _official_ understanding to 
this, but I guess that loading in toplevel is considered as

  - end-user dynamic linking
  - or execution

If we neither build the libraries and toplevel into one binary (via 
ocamlmktop) to distribute, nor do we wrap their source code as a bundle 
for delivery, we don't have to face any license issue. Is that correct?

Then how about a library that explicitly calls some toplevel functions 
(e.g. Topmain.xxx). This might be considered as "intend to link with 
XXX", so must such a library be always released under QPL?  (One 
counterexample might be camlp4, part of which calls toplevel functions 
and is released under LGPL, but it comes from the same team anyway ...)

Another option (if I want to avoid QPL) is to use reflection, so that 
the library don't have to call toplevel functions explicitly, but it 
still requires to work inside a toplevel (or together with a toplevel 
library). However I doubt whether this trick (or say cheating) is 
considered valid. Any precedents?

Thanks.

--
Zheng