BSD 4_3 development

[unix-history] / usr / contrib / icon / src / lib / escape.icn

#       ESCAPE(2)
#
#       Interpret Icon literal strings
#
#       William H. Mitchell
#
#       Last modified 8/14/84
#

procedure escape(s)
  static digits
  initial digits := '0123456789'
  ns := ""
  s ? while c := move(1) do {
     ns ||:=
        if c == "\\" then
        case c2 := (move(1) | "") of {
           "b": "\b"
           "d": "\d"
           "e": "\e"
           "f": "\f"
           "l": "\l"
           "n": "\n"
           "r": "\r"
           "t": "\t"
           "v": "\v"
           "\'": "\'"
           "\"": "\""
           "x": hexcode(move(2))
           "^": ctrlcode(move(1))
           any(digits,c2) & c2: octcode(c2 || move(2))
           "": c
           default: {move(-1); c}
           }
     else c
     }
  return ns
end

procedure hexcode(s)
  return &cset[integer("16r" || s) + 1]
end

procedure octcode(s)
  return &cset[integer("8r" || s) + 1]
end

procedure ctrlcode(s)
  return &cset[find(map(s),&lcase) + 1]
end