Adds instruction for using Build2's package manager

[Klaim]

I created a nlohmann-json package for build2 (https://build2.org) that have been published on the central public repository https://cppget.org : https://cppget.org/nlohmann-json (at the moment you can see that there is only one version: 3.7.3).

The repository of the package code is there: https://github.com/build2-packaging/nlohmann-json and is owned by the build2 community now. (with build2 you can use either a repository like cppget.org or a git repository so both are useful to users for different use cases).

This patch just add the basic information as to how to use this library with build2 to the README file. This is documentation-only.

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[coveralls]

Coverage remained the same at 100.0% when pulling ab538ba on Klaim:patch-1 into ad383f6 on nlohmann:develop.

[nlohmann]

Looks good to me.

[nlohmann]

Thanks a lot! I'll merge once the Travis CI succeeds.

[nlohmann]

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🔖 Release item

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Type

• ✨ New Feature
• 🐛 Bug Fix
• ⚡️ Improvement
• 🔨 Further Change
• 🔥 Deprecated function

Description

• Add support for the build2 package manager. Adds instruction for using Build2's package manager #1909

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[nlohmann]

Thanks!

[nlohmann]

Hi @Klaim, it's been a while that you added the description for build2. Meanwhile, we created a dedicated documentation page for all supported package managers: https://json.nlohmann.me/integration/package_managers/

Unfortunately, I struggle to create a self-contained example how to compile a small example with build2. Can you support me here?

[Klaim]

Sure!

Looking at the other examples, the self-contained exampled should be "from scratch", that is we create a new project and add the library as a dependency. Do I understand correctly?

[nlohmann]

Awesome!

Yes, the idea is to show how to compile the given example.cpp with each package manager. In most cases, this boils down to creating a few other files and then call some commands to get the package and build the project.

[Klaim]

Yeah in the case of build2 it's more usual to use bdep new ... to create the new project as it will generate more files than people tend to expect (necessary for consuming packages + handling the project growing) and setup automatically depending on the options. Also at least one configuration need to be created (similar to cmake's build dir but with the dependencies downloaded and built in there too) for dependencies to be usable.

I'll make a PR soon 👍🏽 Maybe not today, probably tomorrow.

Should I also setup a "summary" box as you did with most other tools?

[nlohmann]

Yes, that would be awesome!