(clojure.set)

The relational set library, reached as alias/var, clojure.set/var, or a referred bare var; each works as a function value too. The algorithms are the oracle's: union grows its largest input, intersection shrinks its smallest, difference and select shrink the first, so an input nothing changes is answered itself and nil stays nil. A relation is a set of maps, records included.

Name	Example	Result
`clojure.set/union`	`(clojure.set/union #{1} #{1})`	`#{1}`
`clojure.set/intersection`	`(clojure.set/intersection #{1 2} #{2 3})`	`#{2}`
`clojure.set/difference`	`(clojure.set/difference #{1 2} #{2})`	`#{1}`
`clojure.set/select`	`(clojure.set/select odd? #{1 2})`	`#{1}`
`clojure.set/project`	`(clojure.set/project #{{:a 1 :b 2}} [:a])`	`#{{:a 1}}`
`clojure.set/rename-keys`	`(clojure.set/rename-keys {:a 1} {:a :b})`	`{:b 1}`
`clojure.set/rename`	`(clojure.set/rename #{{:a 1}} {:a :b})`	`#{{:b 1}}`
`clojure.set/index`	`(clojure.set/index #{{:a 1}} [:a])`	`{{:a 1} #{{:a 1}}}`
`clojure.set/map-invert`	`(clojure.set/map-invert {:a 1})`	`{1 :a}`
`clojure.set/join`	`(clojure.set/join #{{:a 1}} #{{:a 1 :b 2}})`	`#{{:a 1, :b 2}}`
`clojure.set/subset?`	`(clojure.set/subset? #{1} #{1 2})`	`true`
`clojure.set/superset?`	`(clojure.set/superset? #{1 2} #{1})`	`true`