The 'extra' environment marker and its operators

[dustin (Dustin Ingram)]

@uranusjr

Personally I think about the default extra thing not as extras removing thing, but extra groups being activated automatically. So pip install package implies package[default] , and package[other] implies package[default,other] .

I think this is almost right. It’s actually:

• pip install package implies package[(install_requires),default] ,
• pip install package[other] implies package[(install_requires),other] .