[GRASS-user] error message coming with r.colors

[Hamish]

Glynn wrote:
> If reading from stdin remains, it will be via -i, although
> I'm inclined to simply remove the feature altogether
> (it doesn't work well the GUI).

I agree that -i is confusing from the auto-gen GUI.


Please keep the ability to pipe rules from stdin. I use it all the time,
both from the command line and within scripts when it is simple enough
that using a temp file would just be a waste.
e.g. the r.colors.stddev addons script.



I would be happy with removing color=rules and the -i flag *if* 'rules=-'
remained to tell it to expect data from stdin.


> Reading rules from stdin is a substantial deviation from normal
> behaviour. If this feature remains (and I'm not sure that it should),
> it should be a completely separate flag (i.e. -i), not just
> a particular choice for the color= option.

see also v.in.ascii, r.category, r.reclass, r.what, r.what.color, r.profile, ...

we should allow input from stdin for modules which it is useful, and we should do so in a standardized way across all modules. I am happy with the "rules=-" solution; I find adding flags for "expect from stdin" to be unneeded complication and highly confusing to new GUI users.


I wish to make the distinction between removing r.colors "interactive mode" and removing the ability to pipe from stdin rather than from a file.


> I'm considering making color=random a separate flag.

example usage?
  "ERROR: colors= rules= and -random flag are mutually exclusive"
 ???


Hamish