Hi all, i've been trying to construct a regex to help with cleaning up names that can appear in some pretty nasty formats, it's raw data from government agencies. Anyway, one thing i do is look for various 'care of' variants and standardize them to the % symbol. That is done through this regex: 
    $name =~ s/(^|\s)
                    C
                    (\/|\\|%)
                    O
                    (\s|$)
                / % /xgi;

[download]
(yes i am looking for the case of 'C%O' which i also see sometimes)

And then i want to replace forward of backslashes with &, as long as they do not have digits on both sides (which would be a fraction, which does sometimes appear in names i process). That is done through this regex: 

    $field =~ s/(?<!\d)     # not preceeded by digits
                (?:\\|\/)   # back or forward slash
                (?!\d)      # not succeeded by digits
            / & /xg;        # replace with '&' (globally)

[download]
The problem is that sometimes i want to perform only the second transformation without having done the first one, but i could not come up with any decent way to accomplish the second part with the exception of cases that are care-of's, as defined by the first part.

Any thoughts?

Update: I got this working effectively, but then realized that my spec gets even worse, because if i see something like "D/B/A", i want to change that to "DBA" (Doing Business As), so this adds a completely new twist onto when and when not to replace the slashes. So i added this regex after the care of regex: 
    $field =~ s/(?:^|[^A-Z])
                    ([A-Z])\/
                    ([A-Z])\/
                    ([A-Z])
                (?:[^A-Z]|$)
                / $1$2$3 /xig;

[download]
Also, i think that using the separate regexes will work fine, i have worked around the problem of only wanting to perform the final stage without messing the earlier stages. Thanks for all the suggestions!
I use the most powerful debugger available: print!

In reply to Regex Question by shemp

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