Eli Flanagan a473e85c80 docs: document set theory symbols ...

These symbols confused me so I wanted to gloss them to help future users. You can see the context here: https://discourse.nixos.org/t/flakes-what-does-mean-big-bundle-of-questions

2021-11-30 11:13:46 -05:00

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docs: document set theory symbols

2021-11-30 11:13:46 -05:00