Static/shared

[cdunn2001]

(created from several separate branches by @ya1gaurav)

Let's see if it builds....

[cdunn2001]

Let's discuss this now. What was broken? What's the goal of this change?

[ya1gaurav]

The goal of these changes is to use standard CMake variable as option for building either shared/static library. Currently it is using JSONCPP_LIB_BUILD_SHARED & JSONCPP_LIB_BUILD_STATIC.
It will avoid extra variables, as there exists standard variable for same purpose.
Also, as I checked these variables are not used for some other purpose.

[cdunn2001]

According to a comment elsewhere, using the non-standard variables means that this library does not work well as a subproject. Is that your point?

I tried to learn why the custom variables were chosen. It seems to have been arbitrary, in the original (eafd702) commit for cmake build-config.

I think AppVeyor failed a build only because of a problem contacting GitHub. That's fine.

[ya1gaurav]

Actually my motivation is one of the patch i saw - #51
As it is included as work around for standard variable, then why using the other variables like JSONCPP_LIB_BUILD_SHARED, it seems duplicate. Isn't it?

[ya1gaurav]

I have one more question regarding flag "JSON_DLL_BUILD".
DLL are for Windows, is this flag generic for shared library or only for windows in Jsoncpp?
If it is for windows only, should be written under "if(WIN32)".

[cdunn2001]

should be written under "if(WIN32)"

Yes. But it's mingled with the CPPTL code, which I cannot test. I am hoping not to break that since @blep (the original author) still uses it. It's a minor issue.

Thanks for fixing these variables names.

[ya1gaurav]

In Readme file, i can see below:
If JsonCpp was built as a dynamic library on Windows, then your project needs to define the macro JSON_DLL.
It think it means for windows only.