logo/readline.lg

   1 make "backspace_char char 8
   2 make "space_char char 32
   3
   4 to readline :prompt
   5 type :prompt
   6 wait 0         ; flush standard output
   7 localmake "line "
   8 forever [
   9   localmake "c readchar
  10   ifelse emptyp :c [
  11     output []
  12   ] [
  13     localmake "ascii rawascii :c
  14     case :ascii [
  15       [[4]       output []]
  16       [[10]      type :c
  17                  output :line]
  18       [[127]     if not emptyp :line [
  19                    type (word :backspace_char :space_char :backspace_char)
  20                    make "line butlast :line
  21                  ]]
  22       [else      type :c
  23                  make "line word :line :c]
  24     ]
  25   ]
  26 ]
  27 end