+#ifdef _WIN32
+ // On MSVCRT and compatible, output of %e is incompatible to Posix
+ // by default. Number of exponent digits should be at least 2. "%+03d"
+ // FIXME: Implement our formatter to here or Support/Format.h!
+#if __cplusplus >= 201103L && defined(__MINGW32__)
+ // FIXME: It should be generic to C++11.
+ if (N == 0.0 && std::signbit(N))
+ return *this << "-0.000000e+00";
+#else
+ int fpcl = _fpclass(N);
+
+ // negative zero
+ if (fpcl == _FPCLASS_NZ)
+ return *this << "-0.000000e+00";
+#endif
+
+ char buf[16];
+ unsigned len;
+ len = snprintf(buf, sizeof(buf), "%e", N);
+ if (len <= sizeof(buf) - 2) {
+ if (len >= 5 && buf[len - 5] == 'e' && buf[len - 3] == '0') {
+ int cs = buf[len - 4];
+ if (cs == '+' || cs == '-') {
+ int c1 = buf[len - 2];
+ int c0 = buf[len - 1];
+ if (isdigit(static_cast<unsigned char>(c1)) &&
+ isdigit(static_cast<unsigned char>(c0))) {
+ // Trim leading '0': "...e+012" -> "...e+12\0"
+ buf[len - 3] = c1;
+ buf[len - 2] = c0;
+ buf[--len] = 0;
+ }
+ }
+ }
+ return this->operator<<(buf);
+ }
+#endif