if (instr.matches("^\\s*calc\\s+[\\x00-\\xff]*$") || instr.equals("calc")) {
Pattern pattern = Pattern.compile("^\\s*calc\\s+([\\x00-\\xff]*)$");
Matcher matcher = pattern.matcher(instr);
if (matcher.find()) {
Expression e = new Expression(varCollection,matcher.group(1));
wy.format("%s\n",e.calculate());
varCollection=e.getVarCollection();
}
else
throw new ExceptionRPN("calc needs expression");
}