_writeShortestRoundTrip

private fnvoid _writeShortestRoundTrip(double d, ref Appender!string buf) @safe

Write a floating-point value according to opts. Write a finite double as its shortest representation that round-trips.

Tries %.15g, %.16g, %.17g in turn and emits the first output whose re-parse equals the original value — same pattern as the strict JSON writer. Non-finite values must be handled by the caller.

Parameters

`d`	Finite value to format.
`buf`	Output appender.