// Expand # to #{} if in quotes
boolean escaped() {
  pos= textArea.getCaretPosition();
  str= textArea.getText(pos-1, 1);
  return(str.equals("\\"));
}

boolean inQuotes() {
  cl= textArea.getCaretLine();
  str= textArea.getLineText(cl);
  pos= (textArea.getCaretPosition() - textArea.getLineStartOffset(cl))-1;
  cnt= 0;
  do{
    off= str.lastIndexOf("\"", pos);
    if(off < 0)
      break;
    else if(off == 0 || str.charAt(off-1) != '\\')
      cnt++;
    pos= off-1;
  }while(pos >= 0);
  return (cnt & 1) != 0;
}

if((buffer.getMode().getName().equals("ruby") || buffer.getMode().getName().equals("rhtml")) && inQuotes() && !escaped()){
  textArea.setSelectedText("#{}");
  textArea.goToPrevCharacter(false);
}else{
    textArea.setSelectedText("#");
}