No-op Apache mod_rewrite rule

Question

I have an .htaccess file like this:

RewriteCond /question2answer/%{REQUEST_FILENAME} !-f
RewriteCond /question2answer/%{REQUEST_FILENAME} !-d
RewriteCond OTHER_CONDITION_1
RewriteRule RULE_1 [L]

RewriteCond /question2answer/%{REQUEST_FILENAME} !-f
RewriteCond /question2answer/%{REQUEST_FILENAME} !-d
RewriteCond OTHER_CONDITION_2
RewriteRule RULE_2 [L]

...

De Morgan's laws tells me there is a better way to do this:

RewriteCond /question2answer/%{REQUEST_FILENAME} -f
RewriteRule NO-OP [L]
RewriteCond /question2answer/%{REQUEST_FILENAME} -d
RewriteRule NO-OP [L]

RewriteCond OTHER_CONDITION_1
RewriteRule RULE_1 [L]

RewriteCond OTHER_CONDITION_2
RewriteRule RULE_2 [L]    

...

What is the no-op rule that I can use here? And if there are many, I am seeing the one with the least performance impact.

Answer 1

NO_OP (no operation) rule can be this:

RewriteCond %{REQUEST_FILENAME} -f [OR]
RewriteCond %{REQUEST_FILENAME} -d
RewriteRule ^ - [L]

Which means if request is for a file OR if request is for a directory then don't do anything (denoted by - in target URI).