change json inplace

[topolsky]

Hi,

I am trying to implement function to get json, change some part of it and return the changed json.
I thought that its easy.. just parse the json, cast it with AsObject AsArray etc.. change the values inside and then call Stringify on root JSONValue..

But then I found out that the AsObject/AsArray functions are returing const reference which cannot be changed.

I thought that I will use JSONValue::Child() for that but I am not sure if it would work for ::Child(wchar_t*) because there is some const_iterator used..

Is there any way how to achieve inplace change of json easily?
Maybe I overlook/misunderstood something.. sorry for dumb question opening issue..

Also regarding the Child() methods .. why do you not overload subscript [] operator?
Maybe in that way we could just check whats inside JSONValue and go on with [] which would make things easier.. now I have to do the casts all the time which makes it harder to read..

Thanks for your work, I am glad that I do not have to do json stuff myself.. and also your lib compiles on Win XP SP1 which is (sadly) requirement for me :D

[topolsky]

I changed the const_iterator to iterator in Child and added SetNumber (because I need to change number inside JSONObject), now its sort of inplace.. I have to use JSONValue * everywhere and use only Child() to access "nested" structures.

bool JSONValue::SetNumber(double number)
{
    if (!IsNumber()) {
        return false;
    }
    number_value = number;
    return true;
}

I hope that I am not reinventing the wheel.. but it works for me..

[karelv]

I have similar issue, I need to add key-value to "JSONObject".
Then I issued a few time "new JSONValue", and a consequence I have memory leakage :-)
When I try to delete the origital jsonvalue pointer, it deletes also memory which is still needed.

I have both variants:

const JSONObject &JSONValue::AsObject() const
{
	return (*object_value);
}

JSONObject &JSONValue::AsObject()
{
	return (*object_value);
}

and your SetNumber function alikes.

[MJPA]

@karelv have you got an example of what you're trying to do?

Running the following through valgrind gives no memory leaks...

int main(int arc, char ** argv) {
  JSONObject obj;
 
  obj[L"foo"] = new JSONValue(L"bar");
  obj[L"pi"] = new JSONValue(3.141);
    
  JSONValue *json = new JSONValue(obj);
  std::wcout << json->Stringify() << std::endl;
    
  delete json;
  return 0;
}