Option parsing in gdb python

[Robert Lupton the Good]

> The part that I don't get at the moment is how this is all going to be useful in general. Can you give some example of how you want to use this class?

Oh, sorry.  I have an image class, and I want to support
	show image img
but I also want to specify the format width, the part of the image to show, etc.  So

	show image -a img		# print it all
	show image -o 10 20 img 5 5	# print the 5x5 subimage starting at (10, 20)
	show image -o 10 20 -c img 5 5	# print the 5x5 subimage centred at (10, 20)
	show image -f 4 -a img		# print it all, using a field width of 4 chars

That last one looks like:
> (gdb) show image -f 4 -a idImage
>      0 1 2 3 4 5 6 7 8 9 10 11 
> 7    0x0 0x0 0x0 0x3 0x0 0x0 0x0 0x0 0x2 0x2 0x0 0x0 
> 6    0x0 0x0 0x3 0x3 0x3 0x0 0x0 0x2 0x2 0x2 0x2 0x0 
> 5    0x0 0x0 0x0 0x3 0x0 0x0 0x2 0x2 0x2 0x2 0x2 0x2 
> 4    0x0 0x0 0x0 0x0 0x1 0x0 0x0 0x2 0x2 0x0 0x2 0x0 
> 3    0x0 0x0 0x0 0x1 0x1 0x1 0x0 0x0 0x0 0x0 0x0 0x0 
> 2    0x0 0x0 0x1 0x1 0x1 0x1 0x1 0x0 0x0 0x0 0x0 0x0 
> 1    0x0 0x0 0x0 0x1 0x1 0x1 0x0 0x0 0x0 0x0 0x0 0x0 
> 0    0x0 0x0 0x0 0x0 0x1 0x0 0x0 0x0 0x0 0x0 0x0 0x0 

I also have similar needs for eigen::Matrix, and ...

So I call GdbArgumentParse in the invoke method of a subclass of gdb.Command.

					R