[GRASS-dev] GRASS 6.3.0 release preparation

[Glynn Clements]

Michael Barton wrote:

> > We also need to ensure that the wxPython 2.8 package *does* get used
> > by GRASS even though it doesn't get used by anything else which uses
> > wxPython.
> > 
> > Here, I set LD_LIBRARY_PATH and PYTHONPATH manually before running
> > wxgrass. I'm not sure how easy it would be for GRASS to automate that,
> > given that wxPython 2.8 is likely to be installed in such a way that
> > it would normally be "invisible" to packages which use wxPython.
> 
> Good points. I remember some directions at the wxPython download site for
> installing wxPython in non-standard locales and installing multiple
> versions. Maybe we could use those suggestions to deal with this.

It can certainly be done; the issue is the effort required to do it
reliably without user intervention.

Off the top of my head: wxgrass will need to:

1. Catch any exceptions which arise from "import wx" (i.e. no wxPython
as part of the standard Python installation) or "import wx.aui" (i.e. 
wxPython < 2.8).

2. Attempt to locate wxPython 2.8, by looking for directories where it
is likely to be found (i.e. wherever the provided binary packages put
it).

3. Re-invoke itself, after having updated LD_LIBRARY_PATH (or the
equivalent for other platforms) and PYTHONPATH accordingly.

If the user has built wxPython 2.8 themselves, or is using a binary
package installed in a location unknown to #2, they will need to set
LD_LIBRARY_PATH (etc) and PYTHONPATH themselves; that will prevent any
exceptions at #1 (i.e. the package will appear to be part of the
standard wxPython installation so far as wxgrass is concerned).

-- 
Glynn Clements <glynn at gclements.plus.com>