This is the rainbow script i made for fun

f4 { editbox -n /msg $active 1,1 $+ $regsubex($editbox($active),//g,$+($chr(03),$r(0,1),$r(2,9))) }

it does what yours does, but more efficiently just type as you normally would, but use f4 as an enter key.

My more complete one:

rainbow {
  var %rbo 1 , %rb 2 , %txa 
  var %ot $replace($1-,$chr(32),Š) , %rt 1 , %rb $r(2,14)
  while (%rbo < $calc($len(%ot) + 1 )) {
    if (%rb > 15) %rb = 2
    %txa = %txa $+ $($chr(3) $+ %rb) $+ $mid(%ot,%rbo,1)
    inc %rbo
    inc %rb
  }
  msg $active $replace(%txa,Š,$chr(32))
}

this cycles through the colors, so its a true rainbow effect.

also, for the theme I made and use, I use this grammar correction, VERY correct, and works great:

alias wwwww return who what where when why how did will would
alias rere {
  var %x = $1-
  tokenize 32 $1- $+ $iif($1 isalpha,$iif($right($1-,1) !isin $chr(63) $chr(44) $chr(59) :"'!.^][{}(),$iif($1- === $upper($1-),!,$iif($istok($wwwww,$1,32),?))))
  return $iif(%x isupper,$upper($1-),$sentance($1-))
}