code: public static String stripMargin(CharSequence self, CharSequence marginChar) {
          String s = self.toString();
          String mc = marginChar.toString();
          if (mc == null || mc.length() == 0) return stripMargin((CharSequence) s, '|');
          // TODO IllegalArgumentException for marginChar.length() > 1 ? Or support String as marker?
          return stripMargin((CharSequence) s, mc.charAt(0));
      }
docs: Strip leading whitespace/control characters followed by <tt>marginChar</tt> from
  every line in a CharSequence.
  
  @param self       The CharSequence to strip the margin from
  @param marginChar Any character that serves as margin delimiter
  @return the stripped CharSequence
  @see #stripMargin(String, String)
  @since 1.8.2