On Mon, Sep 23, 2019 at 6:44 AM Glen Fernandes wrote:
On Mon, Sep 23, 2019 at 5:19 AM Dominique Devienne via Boost
Also, in client/server communications, it's less often a few huge JSON documents, but rather lots of small documents, so the constant "startup" time of the parser matters too, and in that same vein, a PULL-parser that allows to build the native data-structures directly, rather than the DOM-like approach of fully converting the document to a built-in JSON object, and then convert that to the native-structure, avoids the temp document, which is especially useful for large documents.
It looks like nlohmann/json now has this kind of API too: 1. https://tinyurl.com/nl-json-parse 2. https://tinyurl.com/nl-json-parse-callback
That is the use case that I find more interesting. If you want to decouple your data representation in your program from the serialization format. e.g. In memory if your data structure is something like: vector<map<string, pair<int, double> > >. This could be expressed in json by something like: [ { "key": [1, 0.01], "def": [9, 0.37], ... }, { "xyz": [5, 1.25], "abc": [2, 4.68], ... }, ... ] Your load it from some JSON file. Your don't want to store/use it in your program as a SomeLibrary::JsonArray. Past the point of serialization it should be your own data structures. Of course your could always convert it from SomeLIbrary::JsonArray to your own structures, but that's overhead you don't need if there's hundreds of megabytes worth of content in that data. Glen