on :input:: {
if ($regex($1,^(\+|-)([a-zA-Z])$)) {
var %sign = $regml(1), %mode = $regml(2)
if (%mode isincs cImi) { mode $active $1 }
elseif (%mode isincs vhoaq) {
if (%sign == +) { cs $replacex(%mode,v,voice,h,halfop,o,op,a,protect,q,owner) $active $me }
else { mode $active $1 $me }
}
elseif (%mode isincs QpstACGMKNORSTVu) { mode $active $1 $me }
halt
}
}

quick replacement for the snippet, includes checking to make sure $1 is in the exact format of + or - followed by 1 singular letter...