[m-dev.] Module qualification of typeclass methods

[Peter Ross]

On Wed, Nov 21, 2001 at 12:10:39AM +1100, Simon Taylor wrote:
> On 20-Nov-2001, Peter Ross <peter.ross at miscrit.be> wrote:
> > On Tue, Nov 20, 2001 at 08:08:09PM +1100, Fergus Henderson wrote:
> > > On 30-Oct-2001, Simon Taylor <stayl at cs.mu.OZ.AU> wrote:
> > > > 
> > > > Would it be better to add an `import_package' declaration, which
> > > > is like `import_module', but also imports all sub-modules of the
> > > > imported modules.
> > > 
> > > I like this suggestion better than `:- automatic_import', because it
> > > puts the control over what is imported in the importer rather than
> > > the importee.
> > >
> > I am also happy with this suggestion.  The only difference between the
> > two is that auto_import provides a mechanism to avoid doing to much
> > importing.  However I don't see that as much of an advantage, as I can't
> > see many situations where you don't want all the sub-modules anyway.
> 
> I can. In the .NET class library, the System.Data namespace defines
> a bunch of common classes which are used by the larger sub-namespaces
> for the different data source types.
> 
> The module layout is:
> 
> System.Data
> 	% Classes
> 	Constraint
> 	DataColumn
> 	DataRow
> 	DataTable
> 	etc.
> 
> 	% Larger sub-modules
> 	System.Data.Common
> 	System.Data.OleDb
> 	System.Data.SqlClient
> 	System.Data.SqlTypes
> 	etc.
> 
> If the System.Data.{SqlClient,SqlTypes,OleDb,Common} modules are all used
> then `:- import_package System.Data.*' might be appropriate, but I
> shouldn't be tempted to import everything just to use some of the
> basic classes (DataColumn, etc.) in System.Data. `:- auto_import'
> should be used to import the modules for the basic classes.
> 
I would argue that this is a packaging problem.  The .NET library
designers decided to put all these classes into one deployment unit
(assembly).

I would argue that the namespace pollution issue is due to bad library
design, rather then a problem with the import_package declaration.

Pete
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