Given that perl won't do exactly what you want, perhaps a reasonable compromise is to have it provide a fallback that's easy enough.

Suppose you use your favorite text editor just to create a list of the mixed-case name replacements -- e.g. the self-respecting unix guru would do something like this: 

$ cat > ClRename.sed
s/OldClass/NewClass/g
s/RedClass/BlueClass/g
s/BadClass/GoodClass/g
...
^D

[download]
Now create a version of the list that includes the downcased names along with the original mixed-case ones: 
perl -pe 'print lc' ClRename.sed > flAndClRename.sed

[download]
The latter output file is now suitable for use as a script (for 'perl -pi.bak' or 'sed -f'). Not the most efficient algorithm, perhaps, but usable.

In reply to Re: Preserve Case in Regexp by graff
in thread Preserve Case in Regexp by stefan k

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