niXman

hmm... will look at this...

@Darwinnpos I can't confirm that. the results for me: ``` ==============TEST START=============== data type std::vector size=1000 000 yas time cost: 1.188 ms yas data size: 4.00002 M byte data type...

> I mean why the time cost is different？ ah, got it. will look at that.

@sicheste > Expect: [5e-324] > Actual: [5E-324] is there any reason except aesthetic? and why you are posting it here instead of the boost.json developer project?

> When enabling in main.cpp where is that file?

but according to the JSON grammar: https://www.json.org/json-en.html, the exponent char may be one of `e` or `E`. so from a formal point of view everything is correct here.

first - according to the [doc](https://www.boost.org/doc/libs/1_81_0/libs/json/doc/html/json/ref/boost__json__serialize.html) it seems your example uses `boost::json::serialize(string)` which [call](https://github.com/boostorg/json/blob/master/include/boost/json/impl/serialize.ipp#L97) for [serialize_impl()](https://github.com/boostorg/json/blob/master/include/boost/json/impl/serialize.ipp#L103), [reset(string *)](https://github.com/boostorg/json/blob/master/include/boost/json/impl/serializer.ipp#L784) and finally uses [write_string()](https://github.com/boostorg/json/blob/master/include/boost/json/impl/serializer.ipp#L211) which do nothing with doubles except for escaping...

the `E` comes from here: https://github.com/boostorg/json/blob/master/include/boost/json/detail/ryu/impl/d2s.ipp#L612

no, I haven't tested it. I was just surprised that this instruction was forgotten =)

@CyanoHao could you please provide the PR for the `develop` branch?