Dynamic .htaccess rules

Question

I updated my site twice since the last year and I have different page names since my first version. Is it possible to create dynamic rules in apache?

for example:

I use to have these pages (example):

• /abc123 (version 1)
• /abc_123 (version 2)
• /abc-123/ (version 3 - current)

I want to create a rule that will redirect abc123 to abc_123 if it exists and abc_123 to abc-123 if it exists. Thanks

Answer 1

Why not this?

RewriteRule ^([a-z]+)([0-9]+)$ /$1-$2 [NC,L]
RewriteRule ^([a-z]+)_([0-9]+)$ /$1-$2 [NC,L]

EDIT:

or you can use 1 rule:

RewriteRule ^([a-z]+)(_?)([0-9]+)/?$ /$1-$3 [NC,L]

this way it's easy to add characters in the (_?) instead of creating the same rule over and over with a little variance.