(Double)Real value write as Integer

[dcracker]

Value json;
json["dbl"] = 0.0;
// json["dbl"].type() == realValue

FastWriter writer;
string str = writer.write( json );
// "dbl" becomes 0

Reader reader;
reader.read( str, json );
// json["dbl"].type() == intValue

writer's sprintf with %g doesn't print dot when 0 below.
%lf is OK. but not optimized.
Maybe need to add some codes.
Or am I misunderstand something?

[jacobsa]

I think this is acceptable behavior. JSON doesn't distinguish various sorts of
numbers, so "0" is a reasonable way to represent the double value zero. Ditto
on input: the integer zero is a reasonable way to parse "0". You shouldn't rely
on typing of numbers to round-trip; rather only values.

[dcracker]

OK, now I understand.... maybe?
JSON does not care Integer or Real. They are just part of Number.
And JSON care the Number type. right?
I referenced this site : http://www.json.org

[ondratu]

Hi,
in my opinion that is bad solution.

If is possible to write same output as is read, it could be write. So when you have some clever mechanism to identify number as int, resp. real, you could write real. This do python for example.

I know, that i can retype values to real from int, but for generic reading, type changing is problem.

[cdunn2001]

@ondratu, I don't think this happens for the StreamWriter, does it?

[ondratu]

Yes, here is output from my sample code (build on debian buster with libjsoncpp version 1.7.4):

original:	{"int":78866000000,"real":78866000000.0}
	int type: 2, real type: 3
writed: 	{"int":78866000000,"real":78866000000}
	int type: 2, real type: 2

json.cc

[cdunn2001]

Hmmm. I could be wrong, but I think the most recent commit to master actually appends a . always. Could you try that?

[ondratu]

Yes, master works. Thanks a lot ;-)