t:trimLeft
Description: Removes leading whitespace from a string.
This transformation function removes \x20\t\n\r\f\v characters from the beginning of the input string.
Syntax: t:trimLeft
Implemented: Yes
Example:
# Detect after trimming leading whitespace from parameter
SecRule ARGS:username "@rx ^admin" \
"id:1,phase:2,t:trimLeft,deny,msg:'admin username detected'"
# Original input: " admin"
# After processing: "admin"