[PPL-devel] Unneeded asymmetries between Constraint/Generator public interfaces.

[Roberto Bagnara]

Enea Zaffanella wrote:
> Reasoning on the user interface.
> 
> I noted that the enumeration Type and the corresponding accessor method 
> type() are declared:
> 
>   - public in Generator.defs.hh
>   - PPL_INTERNAL (hence, private for the end-user) in Constraint.defs.hh
> 
> Also, for the class Constraint we do provide boolean tests is_equality() 
> and is_inequality, while similar tests are not provided for Generator: 
> we only have is_line() is declared as PPL_INTERNAL; we don't have 
> methods is_ray() and is_vertex().
> NOTE: the method is_ray_or_vertex() is PPL_INTERNAL, as it should be.
> 
> In order to have a more uniform interface, I suggest the following:
> 
> - let the enums Type and methods type() be public, so that the user has 
> a uniform way to investigate the type of constraints/generators.

I agree.

> - let the boolean tests, including the yet to be written is_ray() and 
> is_vertex(), but excluding is_ray_or_vertex(), be either all public or 
> all PPL_INTERNAL.

I would agree on having them all public (is_line included), even though
I believed we agreed on the fact that the name "vertex" is somewhat special.

> What do you think ? Should I go on and implement this change ?

Please go ahead.

     Roberto

-- 
Prof. Roberto Bagnara
Computer Science Group
Department of Mathematics, University of Parma, Italy
http://www.cs.unipr.it/~bagnara/
mailto:bagnara at cs.unipr.it