add docs for semigroups

toxyduck · toxyduck · commit 1a40c67f5502 · 2019-10-21T19:29:31.000+03:00
diff --git a/core/src/main/java/fj/Semigroup.java b/core/src/main/java/fj/Semigroup.java
@@ -621,14 +621,19 @@ public static <A> Semigroup<IO<A>> ioSemigroup(final Semigroup <A> sa) {
   public static final Semigroup<Unit> unitSemigroup = unitMonoid.semigroup();
 
   /**
-   * A semigroup for sets.
+   * A union semigroup for sets.
    *
    * @return a semigroup for sets.
    */
   public static <A> Semigroup<Set<A>> setSemigroup() {
     return semigroupDef(Set::union);
   }
 
+  /**
+   * A intersection semigroup for sets.
+   *
+   * @return a semigroup for sets.
+   */
   public static <A> Semigroup<Set<A>> setIntersectionSemigroup() {
     return semigroupDef(Set::intersect);
   }

Original file line number	Diff line number	Diff line change
`@@ -621,14 +621,19 @@ public static <A> Semigroup<IO<A>> ioSemigroup(final Semigroup <A> sa) {`
`621`	`621`	`public static final Semigroup<Unit> unitSemigroup = unitMonoid.semigroup();`
`622`	`622`
`623`	`623`	`/**`
`624`		`- * A semigroup for sets.`
	`624`	`+ * A union semigroup for sets.`
`625`	`625`	`*`
`626`	`626`	`* @return a semigroup for sets.`
`627`	`627`	`*/`
`628`	`628`	`public static <A> Semigroup<Set<A>> setSemigroup() {`
`629`	`629`	`return semigroupDef(Set::union);`
`630`	`630`	`}`
`631`	`631`
	`632`	`+ /**`
	`633`	`+ * A intersection semigroup for sets.`
	`634`	`+ *`
	`635`	`+ * @return a semigroup for sets.`
	`636`	`+ */`
`632`	`637`	`public static <A> Semigroup<Set<A>> setIntersectionSemigroup() {`
`633`	`638`	`return semigroupDef(Set::intersect);`
`634`	`639`	`}`