Class WidthHandler

ext/src/cppformat/format.cc:240–264

Checks if an argument is a valid printf width specifier and sets left alignment if it is negative.

// Checks if an argument is a valid printf width specifier and sets
// left alignment if it is negative.
class WidthHandler : public fmt::internal::ArgVisitor<WidthHandler, unsigned> {
 private:
  fmt::FormatSpec &spec_;

 public:
  explicit WidthHandler(fmt::FormatSpec &spec) : spec_(spec) {}

  unsigned visit_unhandled_arg() {
    FMT_THROW(fmt::FormatError("width is not integer"));
    return 0;
  }

  template <typename T>
  unsigned visit_any_int(T value) {
    typedef typename fmt::internal::IntTraits<T>::MainType UnsignedType;
    UnsignedType width = value;
    if (fmt::internal::is_negative(value)) {
      spec_.align_ = fmt::ALIGN_LEFT;
      width = 0 - width;
    }
    if (width > INT_MAX)
      FMT_THROW(fmt::FormatError("number is too big"));
    return static_cast<unsigned>(width);
  }
};

class PrecisionHandler :
    public fmt::internal::ArgVisitor<PrecisionHandler, int> {