There's no need for the f flag either as -c will check the box
I used to use:

alias _load.modes {
  if ($active !ischan) return
  var %mc = $chan($active).mode
  if (m isincs %mc) did -c _options 52 
  if (N isincs %mc) did -c _options 78
  if (I isincs %mc) did -c _options 43 
  if (R isincs %mc) did -c _options 44 
  if (L isincs %mc) did -c _options 45 
  if (f isincs %mc) did -c _options 46 
  if (G isincs %mc) did -c _options 76 
  if (C isincs %mc) did -c _options 77 
  if (n isincs %mc) did -c _options 71 
  if (t isincs %mc) did -c _options 70 
  if (Q isincs %mc) did -c _options 81
  if (c isincs %mc) did -c _options 73 
  if (M isincs %mc) did -c _options 82
  if (T isincs %mc) did -c _options 79
  if (j isincs %mc) did -c _options 60 
  if (w isincs %mc) did -c _options 61 
  if (p isincs %mc) did -c _options 80
  if (l isincs %mc) did -i _options 84 1 * $gettok(%mc,-1,32)
  if (K isincs %mc) did -c  _options 72 
  if (R isincs %mc) did -c _options 74 
}

but even then I don't like it, it's too long and messy for such basic code. $iif would work just as well to clean it up as well.