Question

I have found some very useful code:

RewriteEngine On
RewriteCond %{HTTP_HOST} ^www.example.com$ [NC]
RewriteRule ^(.*)$ http://example.com/$1 [R=301,L]

from another Stack Overflow post:
Remove WWW prefix from your website.

I often re-use the same code on various sub-domains and sites so decided to rewrite a generalised version. I came up with the following:

RewriteEngine On
RewriteCond %{HTTP_HOST} ^www\.(.*) [NC]
RewriteRule ^(.*)$ http://%1/$1 [R=301,L]

It appears to work, but can anyone give me a reason why I should not use this? Have I missed an obvious flaw?

Edit: I am aware that removing the www has associated issues, but in this case I am more interested in problems arising from writing a generalised htaccess RewriteRule (rather than the actions of the rule itself)

Edit: Code edited as recommended by @ulrich

Answer 1

I would also escape the. otherwise it would match www2.somedomain.com and your %1 would end up being .somedomain.com (if you had such a subdomain configured in the future)

RewriteCond %{HTTP_HOST} ^www\.(.*) [NC]

If you want to further limit it to just a .com you could use

RewriteCond %{HTTP_HOST} ^www\.(.+\.com)$ [NC]

or .net etc

RewriteCond %{HTTP_HOST} ^www\.(.+\.(com|net|edu))$ [NC]

You may also want to add a RewriteBase / after the RewriteEngine On in case you add other rules to your .htaccess later that need it.

Barring those cases, it should work as is.