private void validateNumberString(String numberString) throws MDException {
		numberString.getBytes();
		for (int c : numberString.getBytes()) {
			if (!Character.isDigit(c)) { // includes end of string (MDMang.DONE)
				throw new MDException("Illegal character in Number: " + c);
			}
		}
	}
Validates Number (it is output as Number << '@' where Number is an unsigned int, so we are
 capturing it as a string of digits.
 Built for what seems to be LLVM-specific mangling.  Does not follow MSFT model.
@throws MDException Upon invalid character sequence or out of characters.
Ghidra/Features/MicrosoftDmang/src/main/java/mdemangler/naming/MDReusableName.java