Function HexDigitToInt

internal/strings.cc:37–42

constexpr char kHexTable[] = "0123456789abcdef";

constexpr int HexDigitToInt(char x) {
  if (x > '9') {
    x += 9;
  }
  return x & 0xf;
}

constexpr bool IsOctalDigit(char x) { return x >= '0' && x <= '7'; }