[Tutor] how to match regular expression from right to left

[Kent Johnson]

$B2&D6(B wrote:
> yes, but I mean if I have the line like this:
> 
> line = """38166 us::Video_Cat::Other; us::Video_Cat::Today Show; 
> us::VC_Supplier::bc; 1002::ms://bc.wd.net/a275/video/tdy_is.asf; 
> 1003::ms://bc.wd.net/a275/video/tdy_is_.fl;"""
> 
> I want to get the part "us::MSNVideo_Cat::Other; us::MSNVideo_Cat::Today 
> Show; us::VC_Supplier::Msnbc;"
> 
> but re.compile(r"(us::.*) .*(1002|1003).*$") will get the 
> "1002::ms://bc.wd.net/a275/video/tdy_is.asf;" included in an lazy mode.

Of course, you have asked for all the text up to the end of the string.

Not sure what you mean by lazy mode...

If there will always be three items you could just repeat the relevant
sections of the re, something like

r'(us::.*?); (us::.*?); (us::.*?);'

or even

r'(us::Video_Cat::.*?); (us::Video_Cat::.*?); (us::VC_Supplier::.*?);'

If the number of items varies then use re.findall() with (us::.*?);

The non-greedy match is not strictly needed in the first case but it is
in the second.

Kent