RE question; how to insert a digit between const[a-z]*3 && inc[0-9]*3?

taint has asked for the wisdom of the Perl Monks concerning the following question:

Greetings, I've been maintaining some 9k html records for a few years now. The names of the files begin with the same 3 alpha characters, followed by 4, or less digits (0-9). I've been maintaining them via quick one-off sed scripts. But recently I decided I needed to re-numerate them, as it would be ultimately be more efficient. I also decided (given I /really/ love perl) that it would make more sense to maintain a set of Perl scripts to better maintain these documents, then it hit me -- I have no idea how to take on the task of re-numerating the references within these documents.
PROBLEM:

changing all references to:
abc[0-9][0-9][0-9].html
into
abc0[0-9][0-9][0-9].html

the same goes for abc[0-9][0-9].html
in short; I need all of the files to be 4 digits long -- not 1,2, & 3, as they are now.
I'm fair with search & replace, add, and delete. But I /suck/ at hold patterns -- which I think I need here. I tried to match against:

 /abc1[0-9][0-9].html

with the intent of matching within the 100-199.html documents. But all my efforts were an epic fail.
Pointers, solutions would be greatly appreciated.

Thank you for all your time, and consideration.

#!/usr/bin/perl -Tw
use perl::always;
my $perl_version = "5.12.4";
print $perl_version;

Comment on RE question; how to insert a digit between const[a-z]3 && inc[0-9]3?

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Re: RE question; how to insert a digit between const[a-z]3 && inc[0-9]3? (sprintf) by tye (Sage) on Apr 16, 2013 at 01:10 UTC
`s{(?<=[a-z])([0-9]{1,3})(?=[.])}{ sprintf "%04d", $1 }ge;` [download] ...with whatever additions are needed near the start and end of that regex in order to only match the parts that you want to. - tye	[reply] [d/l]
Re^2: RE question; how to insert a digit between const[a-z]3 && inc[0-9]3? (sprintf) by hdb (Monsignor) on Apr 16, 2013 at 06:43 UTC
Can it not be as simple as `s{abc(\d+)\.html}{sprintf("abc%04d.html",$1)}ge;` [download] if all the filenames are of the form abc\d+.html or is there a catch?	[reply] [d/l]
Re^3: RE question; how to insert a digit between const[a-z]3 && inc[0-9]3? (sprintf) by tye (Sage) on Apr 16, 2013 at 13:54 UTC
I doubt "abc" was as literal as you interpreted it to be. - tye	[reply]
Re^4: RE question; how to insert a digit between const[a-z]3 && inc[0-9]3? (sprintf) by taint (Chaplain) on Apr 16, 2013 at 16:21 UTC
Re^5: RE question; how to insert a digit between const[a-z]3 && inc[0-9]3? (try) by tye (Sage) on Apr 16, 2013 at 16:36 UTC
Some notes below your chosen depth have not been shown here
Re^2: RE question; how to insert a digit between const[a-z]3 && inc[0-9]3? (sprintf) by taint (Chaplain) on Apr 16, 2013 at 16:58 UTC
Greetings tye. Thanks for taking the time to respond. `s{(?<=[a-z])([0-9]{1,3})(?=[.])}{ sprintf "%04d", $1 }ge;` [download] Looks brilliant in it's simplicity. But my head is still in sed(1) scripting mode. So I fear I am not yet following it. :( I'm attempting to sort it out now. :) Thanks again! #!/usr/bin/perl -Tw use perl::always; my $perl_version = "5.12.4"; print $perl_version;	[reply] [d/l]
Re: RE question; how to insert a digit between const[a-z]3 && inc[0-9]3? by kcott (Archbishop) on Apr 16, 2013 at 11:35 UTC
G'day taint, Here's another way to do it: `$ perl -Mstrict -Mwarnings -E ' my @files = qw{abc1.html abc12.html abc123.html abc1234.html}; say for map { s/^(abc)(\d{1,3})(\.html)$/$1 . "0" x (4 - length $2) . $2 . $ +3/e; $_ } @files; ' abc0001.html abc0012.html abc0123.html abc1234.html` [download] Update: "... the files begin with the same 3 alpha characters ..." so `\w{3}` is far too generic: `s/\w{3}/abc/` -- Ken	[reply] [d/l] [select]
Re^2: RE question; how to insert a digit between const[a-z]3 && inc[0-9]3? by taint (Chaplain) on Apr 16, 2013 at 17:53 UTC
Greetings Ken, and thanks for the reply. This looks like a complete solution! Given that all of the files end in `.html`, and begin with `abc` I should be able to simply read in the entire directory. `opendir(DIR, $dirname) or die "can't opendir $dirname: $!"; while (defined($file = readdir(DIR))) { # use your suggestion on "$dirname/$file" } closedir(DIR);` [download] I'm still sorting it all out. But wanted to take the time to thank you for your help. Thanks again! --chris #!/usr/bin/perl -Tw use perl::always; my $perl_version = "5.12.4"; print $perl_version;	[reply] [d/l]
Re^3: RE question; how to insert a digit between const[a-z]3 && inc[0-9]3? by kcott (Archbishop) on Apr 16, 2013 at 19:50 UTC
Given that context, you might want to try something like this technique (untested): `while (defined($file = readdir(DIR))) { next unless $file =~ /^(abc)(\d{1,3})(\.html)$/; rename "$dirname/$file" "$dirname/" . $1 . "0" x (4 - length $2) . + $2 . $3; }` [download] I'd also recommend that you try this with a print to ensure you're in the right directory and targetting the correct files before making thousands of changes; then change to rename. Some error checking/handling might also be useful. -- Ken	[reply] [d/l]
Re^4: RE question; how to insert a digit between const[a-z]3 && inc[0-9]3? by taint (Chaplain) on Apr 16, 2013 at 22:09 UTC
Re: RE question; how to insert a digit between const[a-z]3 && inc[0-9]3? by MidLifeXis (Monsignor) on Apr 16, 2013 at 13:36 UTC
Depending on your server software, you could also configure your server to generate a 301 response for the old document names. I have done this in the past on apache with mod_rewrite. It could also be done with a mod_perl handler or even a dispatcher if you drive everything through a dispatch script. --MidLifeXis	[reply]