what does this regexp means?

[laruence]

located in "./admin/includes/application_top.php"
line 121:
$loaderPrefix = preg_replace('/[a-z_]^/', '', $loaderPrefix);

what does this pattern "/[a-z_]^/" means?

spell mistake?

[DrByte]

No, that's not an error. It's very specific.
It's stripping invalid characters from the passed parameter.
More information on regex: http://www.regular-expressions.info/reference.html
and the PHP preg_replace() function: http://www.php.net/manual/en/function.preg-replace.php

[laruence]

/[a-z_]^/ this caret means what? thanks

[DrByte]

In that case, the caret is a negation operator. So, that preg_replace statement replaces any characters not matching a-z or underscore with blanks, effectively removing bad characters.

[laruence]

In that case, the caret is a negation operator. So, that preg_replace statement replaces any characters not matching a-z or underscore with blanks, effectively removing bad characters.

you means [^a-z_] ?

[laruence]

var_dump(preg_match('/[a-z_]^/',"A"))

result is false

[DrByte]

Are you running into a particular problem with your store?