src/main/java/wycc/cfg/ConfigFileLexer.java
public Token scanNumericConstant() {
		int start = pos;
		while (pos < input.length() && Character.isDigit(input.charAt(pos))) {
			pos = pos + 1;
		}
		return new Token(Token.Kind.IntValue, input.substring(start, pos),
				start);
	}
public Token scanNumericConstant() {
		int start = pos;
		while (pos < input.length() && Character.isDigit(input.charAt(pos))) {
			pos = pos + 1;
		}
		return new Token(Token.Kind.IntValue, input.substring(start, pos),
				start);
	}
Scan a numeric constant. That is a sequence of digits which gives either
an integer constant, or a real constant (if it includes a dot) or a byte
(if it ends in a 'b').

@return