RewriteRule ^/(.*.(php|html|htm|css|jpg))$ /$1 [NC,L]
    RewriteRule ^/(.*)$ /bar.php?code=$1 [NC,L]

RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php

$url_array = split('/', $_SERVER['REQUEST_URI']);
array_shift($url_array); // remove first value as it's empty

RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^/([^.]+)$ /bar.php?code=$1 [QSA,L]

RewriteCond %{REQUEST_URI} ^/blerg$
RewriteRule ...

RewriteCond %{REQUEST_URI} ^/blerg$
RewriteRule ...

RewriteRule ^/(.*.(php|html|htm|css|jpg))$ /$1 [NC,L]
RewriteRule ^/$ /index.php [L]
RewriteRule ^/(.*)$ /bar.php?code=$1 [NC,L]

RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.+)$ /handler.php?request=$1 [QSA,L]

RewriteRule ^blah.jpg$ /some_other_file.jpg [L]

RewriteRule ^directory/?$ /some_other_directory/index.php [L]

RewriteRule ^/(.*)$ /bar.php?code=$1 [NC,L]

RewriteRule ^/?(.*)$ /bar.php?code=$1 [NC,L]