Project:Python/PYTHON TARGETS

PYTHON_TARGETS and PYTHON_SINGLE_TARGET are Article description:: [[USE_EXPAND variables controlling support for various Python implementations (versions) in packages.]] These essentially control what version of Python the package will reference during and after installation.

Enabling Python implementations
The modern packages (using -r1 suite eclasses) use explicit USE flags aggregated in PYTHON_TARGETS and PYTHON_SINGLE_TARGET USE_EXPAND variables. The variables are defaulted in profiles and can be changed in. The flags may be adjusted per-package using as well.

The PYTHON_TARGETS variable is used for packages that support enabling more than a single Python implementation. Therefore, the variable may contain any number of implementations.

The PYTHON_SINGLE_TARGET variable is used for packages that are built for a single implementation of choice only. It may contain only a single implementation. Due to technical limitations, the implementation specified as PYTHON_SINGLE_TARGET must also be included in PYTHON_TARGETS for the package in question.

The possible values are listed in the PYTHON_COMPAT column of the Python project's implementations list.

Unmasking non-stable implementation on a stable system
If you'd like to use an implementation that is not stable on your architecture on a stable system, you need to:


 * 1) Unmask the implementation using ,
 * 2) Unmask the relevant USE flags using . This also requires to set  to EAPI >= 5.