remove and disallow extensions with .htaccess - php

Question

I found this script or removing extensions from php files:
RewriteEngine On
RewriteCond %{REQUEST_FILENAME} !-f
RewriteRule ^([^\.]+)$ $1.php [NC,L]
While this works, it still allows files to be accessed if you type them in with their extension, which I don't want.
I tried the following:
RewriteEngine On
RewriteCond %{REQUEST_FILENAME} !-f
RewriteRule ^([.]+)$ $1.php [NC,L]
I also tried ^(.*)$ and ^(.+)$
which seems like it should do the job, because it would do this:
index.php -> index.php.php
but somehow, it doesn't work as expected.
So how do I update the above .htaccess script to disallow file extensions?
EDIT:
My .htaccess script seems to be detecting the files correctly:
RewriteEngine On
RewriteCond %{REQUEST_FILENAME} -f
RewriteRule "^.*\.php$" "other.html" [L]
RewriteRule "^([^\.]+)$" "other2.html" [L]
The pages other.html and other2.html simply contain the words "OTHER" and "OTHER 2"
Now, using the above script, the output is as expected:
"/test.php" gives output "OTHER"
"/test" gives "OTHER 2"
but if I update the script to the following, both url variations start returning "OTHER"
RewriteEngine On
RewriteCond %{REQUEST_FILENAME} -f
RewriteRule "^.*\.php$" "other.html" [L]
RewriteRule "^([^\.]+)$" "$1.php" [L] // changed
So it seems that after the extensionless filename has ".php" added to it by rule#2, it somehow gets caught by rule #1.
Aren't these rules ordered? and isn't [L] supposed to stop processing on a match?
EDIT 2:
So assuming [L] did what I was expecting... the following script would work...
RewriteEngine On
RewriteCond %{REQUEST_FILENAME} -f
RewriteRule "^.*\.php$" "404.html" [L]
RewriteRule "^([^\.]+)$" "$1.php" [L]

Answer 1

Try this solution How to remove file extension from website address?
RewriteEngine on
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME}\.php -f
RewriteRule ^(.*)$ $1.php
edit: you can do a filematch to prevent executing all .php except index.php. I typically route most of my pages through index.php anyways so this solution would work if you only have a handful of base index files (index1.php,index2.php,etc). I'm sure you can come up with something from this if you don't find a working solution.
<FilesMatch "\.php$">
Order Allow,Deny
Deny from all
</FilesMatch>
<FilesMatch "index[0-9]?\.php$">
Order Allow,Deny
Allow from all
</FilesMatch>

Answer 2

This works:
RewriteEngine On
RewriteCond %{REQUEST_FILENAME} -f
RewriteRule "^.*\.php$" "404.html" [END]
RewriteRule "^([^\.]+)$" "$1.php" [END]