Now currently I got a generic anti-flood script to work...
But I want to modify it to include a detection of the same line from any user being entered, no matter of time interval. Problem is, I'm pretty new to scripting, so I figured I'd ask here for help since I don't know what I'd put.

Here's what I got on my anti-flood script so far. I'd like to achieve the same end result, except for duplicate lines no matter how far apart they are...How would I add a check for that?
; Kicks on flooding any 3 lines in 2 seconds.
on @*:TEXT:*:#:{
inc -u2 %flood. [ $+ [ $nick ] ]
if (%flood. [ $+ [ $nick ] ] == 3) {
ban -ku600 $chan $nick 3 Tell ya what... Stop floodin. Take a timeout for 10 minutes!
halt
}
}