add co/2.0.2

[idealvin]

Specify library name and version: lib/1.0

This is also a good place to share with all of us why you are submitting this PR (specially if it is a new addition to ConanCenter): is it a dependency of other libraries you want to package? Are you the author of the library? Thanks!

---

• I've read the guidelines for contributing.
• I've followed the PEP8 style guides for Python code in the recipes.
• I've used the latest Conan client version.
• I've tried at least one configuration locally with the
  conan-center hook activated.

[CLAassistant]

All committers have signed the CLA.

[idealvin]

@prince-chrismc

All blue! Can it be merged into one piece now?

Thanks for your help!

[prince-chrismc]

Why wouldn't we use the latest?

Can users choose the version by themselves?

Absolutely they can!

https://docs.conan.io/en/latest/using_packages/conanfile_txt.html#overriding-requirements

[prince-chrismc]

And one more questions

Does this impact the features?
https://github.com/idealvin/co/blob/7be5367623a85ca8a0a4e2095000d7b704cc9f89/src/CMakeLists.txt#L94

How can a consumer know if this was enabled?

[prince-chrismc]

Are we fine with co? Perhaps it 's safer to namespace it? idealvin-co?

I think it's a great idea, people who aren't familiar with the project we get confused

[prince-chrismc]

Why is this upper case?

Look at at the code it should be lowercase https://github.com/idealvin/co/blob/7be5367623a85ca8a0a4e2095000d7b704cc9f89/src/CMakeLists.txt#L112?

[idealvin]

Fixed. Thanks.

[idealvin]

Are we fine with co? Perhaps it 's safer to namespace it? idealvin-co

Unfortunately, I chose the name co at the beginning, and it’s too late when I want to rename it.

[uilianries]

I didn't find other C/C++ projects using same name. As your project has 2k2 stars on GIthub, it's popular, so I think is okay accepting it as co only.

[idealvin]

I didn't find other C/C++ projects using same name. As your project has 2k2 stars on GIthub, it's popular, so I think is okay accepting it as co only.

Thanks!

[idealvin]

And one more questions

Does this impact the features? https://github.com/idealvin/co/blob/7be5367623a85ca8a0a4e2095000d7b704cc9f89/src/CMakeLists.txt#L94

How can a consumer know if this was enabled?

This is described in the documents, should be ok.

[prince-chrismc]

This is described in the documents, should be ok.

Then libstacktrace needs to be an option. Otherwise Conan wont be able to track it

[idealvin]

This is described in the documents, should be ok.

Then libstacktrace needs to be an option. Otherwise Conan wont be able to track it

@prince-chrismc

This is a little different, libbacktrace is automatically detected by check_include_files in cmake:

    check_include_files(backtrace.h HAS_BACKTRACE)
    if(HAS_BACKTRACE)
        target_compile_definitions(co PRIVATE HAS_BACKTRACE_H)
        target_link_libraries(co PUBLIC backtrace)
    endif()

It seems that it is not necessary for conan to track it.

[prince-chrismc]

This is a little different, libbacktrace is automatically detected by check_include_files in cmake:

Okay, there's a key feature about Conan that makes it so powerful.
➡️ its ability to calculate the package_id

Now what the hell does that mean?
https://docs.conan.io/en/latest/reference/conanfile/methods.html#package-id

TL;DR it is related to the ABI of the binary. Well mostly.

That means anything that affect the binary, add/removes API, compiler settings, platform, etc need to be tracked by conan.
This is done for a lot by default but certain details (like what optional dependencies maybe be used) need to be added as options.

I'll give you an example where not adding the option may ruin someone's day.

We have two systems

1. The builder -- for some unknown reason has libbacktrace is installed
2. A costumers system who runs our application

When we build our app we are going to compile and link against libbacktrace. Unit tests will pass. Everything is ready.
The customer runs the applications and gets "unable to load libbacktrace.so"

The opposite is less annoying but easily avoided... let pretend we forgot to install the extra library. if the option with_backtrace was true the compilation would fail since it was missing.

[idealvin]

@prince-chrismc
Usually, libbacktrace has been installed within gcc as a static library if you have a newer version of gcc on linux, and you may find it in a directory like /usr/lib/gcc/x86_64-linux-gnu/9.

I think there is no problem at present. However, I'll consider make it as a feature in the next version of co.

[conan-center-bot]

All green in build 29 (3c4fe47dedabeaaf6af5487750336bbcc9771b18):

• co/2.0.2@:
  All packages built successfully! (All logs)

[uilianries]

LGTM