Summary: | [Future EAPI] USE-dependent USE-flag masking | ||
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Product: | Gentoo Hosted Projects | Reporter: | Matt Turner <mattst88> |
Component: | PMS/EAPI | Assignee: | Package Manager Specification <pms> |
Status: | CONFIRMED --- | ||
Severity: | normal | CC: | eschwartz, esigra, gentoo, kuraga333, sam |
Priority: | Normal | ||
Version: | unspecified | ||
Hardware: | All | ||
OS: | Linux | ||
See Also: | https://bugs.gentoo.org/show_bug.cgi?id=609338 | ||
Whiteboard: | |||
Package list: | Runtime testing required: | --- | |
Bug Depends on: | |||
Bug Blocks: | 174380 |
Description
Matt Turner
![]() A REQUIRED_USE extension might fit better, since that already specifies relationships between flags. I independently thought about the topic and found this bug when searching for existing proposals. GLEP 73 is related but a very complicated way to solve the problem and doesn't seem to be progressing... (In reply to Zac Medico from comment #1) > A REQUIRED_USE extension might fit better, since that already specifies > relationships between flags. My original idea didn't use IUSE but rather MASKED_USE="python? ( python_single_target_python3_{7..9} )" Making it part of REQUIRED_USE itself doesn't make sense IMO. In the case of REQUIRED, it is up to the user to say what they want and guarantee it is available. The PM doesn't know (absent GLEP 73 "guess a suitable default") which implementation you actually want, just that you do want one. But in the case of MASKED, the PM knows with 100% accuracy what you want: you want to mark all python_single_target_python3_{7..9} flags as disabled, since they are not *checked* by any ebuild code when USE="-python". There should be no guesswork involved. It's a direct instruction that all these USE flags shall be toggled off. This functionality would also be very useful for binary repositories to avoid cache key failures, since packages without USE=python are still tied to some arbitrary value of PYTHON_TARGETS / PYTHON_SINGLE_TARGET at the time of building. Also, it's not just python that this is relevant to, but other programming languages that can be optionally supported by a package: llvm, lua, ruby, php, postgres, and now guile as well. |