Forth optimization

: of
  postpone over  postpone =
  postpone if  postpone drop ; immediate

\ taken from published Forth code
: Esc1 ( -- flag )
  key? if
     key 27 = if
        true
     else
        false
     then
  else
     false
  then
;

: Esc2 ( -- flag )
  key? if
     key 27 =
  else
     false
  then
;

: Esc3 ( -- flag )
  key? if  key 27 =  exit  then  false
;

: Esc4 ( -- flag )
  key? -1 of  key 27 =  then
;