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Stream: learning: questions

Topic: presheaves and injectivity classes

Jan Pax (Aug 14 2022 at 14:19):

I have a rather informal question:
I would like to know how a small injectivity class in a presheaf category ${\mathbf{Set}^{\cal A}}^{op}$ for $\cal A$ small formally looks like and also, besides some trivial example cases that could be given, how it can be used in a proof.The same would be good to know for a small cone-injectivity class.