(If I understand correctly)
This "(^,$)" should be parsed as a list of useful "anchor" symbols (resp. start and end of string) rather than a regexep itself. I wasted some time before I realised this.
This "(^,$)" should be parsed as a list of useful "anchor" symbols (resp. start and end of string) rather than a regexep itself. I wasted some time before I realised this.
Since we are engine agnostic here be careful interpreting ^ or $ as start/end of _string_ though. In some regex engines this means start/end of _line_. If that's the case and if a regex validates input up to $ an attacker might be able to sneak in extra data after a newline. In Python you'd need multiline enabled but Ruby matches by default:
irb(main):001:0> /^okay$/ =~ "okay\noops"
=> 0 # matches from position 0