Some proplist helpers
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Delete all properties named foo or bar:
1> proplutils:delete([foo, bar], [{foo, "does"}, {bar, "not"}, {baz, "matter"}]).
[{baz,"matter"}]
Delete all properties that aren't named foo or bar:
1> proplutils:delete_except([foo, bar], [{foo, "does"}, {bar, "not"}, {baz, "matter"}]).
[{foo,"does"},{bar,"not"}]