Sure, but you need to be root to install those, they're not portable, and there's no workspace isolation or build system consistency— yes CMake has bridge methods to work with autotools/pkg-config, but it's all pretty hacky.

For a tool that does attempt to do virtualenv-like workspaces for C++ packages, see colcon [1], but there are still a lot of rough edges there— it's an evolution of the catkin multi package build system/tool from the ROS ecosystem, and part of the promise of it is a pluggable mechanism for discovering the packages in your workspace to avoid needing to a patch in a special XML file containing dependency information.

[1]: https://colcon.readthedocs.io/

> C++ does have a standard package manager. It's the system package manager, instead of a language-specific one.

So C++ does not have a standard package manager.

Or are we really going full HN and debating the meaning of the word standard? Even if we are... is there a standard system? For that standard system, is there a standard package manager?

You're the only one trying to play with definitions of "standard" here. The system package manager was the standard packaging method for extra functionality on Linux (and other) systems regardless of implementation language before perl/Python/etc. started coming up with their own. You might argue that it's a bad standard, that it doesn't work for more "nimble" languages, whatever, but it is how C++ code is supposed to be packaged and has been for a long time. What C++ doesn't have is an exclusive package manager that can't be used with other languages. Non-exclusivity doesn't make anything less standard. Quite the contrary.