[GRASS5] Inconsistencies among modules

Eric G. Miller egm2 at jps.net
Wed Aug 8 23:29:12 EDT 2001


On Wed, Aug 08, 2001 at 12:47:19PM -0700, Rich Shepard wrote:
>   Two inconsistencies I've picked up:
> 
>   1)  Some modules (e.g., r.in.gdal, r.patch) allow the use of an existing
> output file name with no warning that that file already exists, and asking
> the user if it's OK to overwrite it. Other modules (e.g., r.poly, v.digit)
> tell the user that the output file name exists, does not ask for directions,
> and refuses to let the user overwrite it. Recommendation: always check,
> always ask, follow the user's directions.

I don't know if there is a correct behavior.  My personal feeling is
that modules should not overwrite existing files unless explicitly told
to do so (such as with a force flag).  It's much easier to handle the
overwrites with raster files than with vector files (which actually have
several related files).  I don't like the idea of the prompt after
initial argument parsing because it interferes with the potential to
create graphical front-ends to commands (of course, several commands
still currently expect a terminal for post-parser input at this point
anyway).

>   2)  Most modules present a status indication of processing; usually the
> percentage completed. Other modules (today it was r.poly) give no indication
> whether they are slowly working or have silently passed away.
> Recommendation: have a progress indicator for all modules.

Not always possible or meaningful.  Vectors don't lend themselves to
meaningful percentages necessarily as parts can vary in size and
complexity.  Also, it's not always easy to work in the G_percent() calls
without drastic rewrites of a module (and still may not be possible).
But, progress can still be indicated textually ("Doing foo..", "Doing
bar..", etc...).

-- 
Eric G. Miller <egm2 at jps.net>



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