Union is called in docs

Author: odow

src/Nonlinear/ReverseAD/Coloring/Coloring.jl

@@ -45,6 +45,13 @@ end
 
 Base.collect(v::IndexedSet) = v.nzidx[1:v.nnz]
 
+function Base.union!(v::IndexedSet, s)
+    for x in s
+        push!(v, x)
+    end
+    return
+end
+
 # compact storage for an undirected graph
 # neighbors of vertex i start at adjlist[offsets[i]]
 struct UndirectedGraph