Return just matched strings with grep

When filtering output with grep, the flag -o can be used to return only the matched parts of a line. The flag -h can be used to suppress the filename for each match.

To run eslint on a repo and find which typescript-eslint rules currently have infractions, you can sort and then take uniques of the matches returned by grep with the aforementioned flags:

$ npx eslint . | grep -oh "@typescript-eslint/.*" | sort | uniq

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