         @lowSurrogateChar.source
     )
     # Characters Not Ending a Line and High Surrogate
-    @notEndingChar = new RegExp(
+    @notEndingCharRegexp = new RegExp(
         @openingBracketChar.source + "|" +
         @highSurrogateChar.source
     )
 
     # Character Width
-    @zeroWidthChar = /[\u200B-\u200F\uDC00-\uDFFF\uFEFF]/
-    @halfWidthChar = /[\u0000-\u036F\u2000-\u2000A\u2122\uD800-\uD83F\uFF61-\uFFDC]/
+    @zeroWidthCharRegexp = /[\u200B-\u200F\uDC00-\uDFFF\uFEFF]/
+    @halfWidthCharRegexp = /[\u0000-\u036F\u2000-\u2000A\u2122\uD800-\uD83F\uFF61-\uFFDC]/
     # @fullWidthChar = /[^\u0000-\u036F\uFF61-\uFFDC]/
 
   # overwrite Display#findWrapColumn()

    return unless (line.length * 2) > sotfWrapColumn
    size = 0
    for wrapColumn in [0...line.length]
      if @zeroWidthChar.test(line[wrapColumn])
        continue
      else if @halfWidthChar.test(line[wrapColumn])
        size = size + 1
      else
        size = size + 2

      if size > sotfWrapColumn
        if @notEndingChar.test(line[wrapColumn - 1])
          # search backward for the not ending character
          for column in [(wrapColumn - 1)...0]
            return column unless @notEndingChar.test(line[column - 1])
          return wrapColumn
        else if @whitespaceChar.test(line[wrapColumn])
          # search forward for the start of a word past the boundary

    @westernChar = /[\u0021-\u007E\u00A0-\u1FFF]/

    # Characters Not Starting a Line and Low Surrogate
    @notStartingCharRexgexp = new RegExp(
        @closingBracketChar.source + "|"  +
        @hyphenChar.source + "|" +
        @dividingPunctuationChar.source + "|" +
