Function isDigit

src/fl/stl/istream.cpp.hpp:14–16

Helper function to check if a character is a digit

namespace {
    // Helper function to check if a character is a digit
    inline bool isDigit(char c) {
        return c >= '0' && c <= '9';
    }
    
    // Helper function to check if a character is whitespace
    inline bool isSpace(char c) {