Add bin and edit workflow

bin/gems/facets-3.1.0/lib/standard/facets/set.rb

@@ -0,0 +1,36 @@
+require 'set'
+
+class Set
+
+  #
+  # @author Phrogz
+  def power_set
+    if empty?
+      Set[self]
+    else
+      any_value = [to_a.first]
+      subsubs = (self - any_value).power_set
+      subsubs + subsubs.map{ |subset| subset + any_value }
+    end
+  end
+end
+
+class Array
+
+  # TODO: Move to Array extensions.
+
+  #
+  # @author Phrogz
+  def power_set
+    if empty?
+      [self]
+    else
+      subset  = dup
+      value   = [ subset.pop ]
+      subsubs = subset.power_set
+      subsubs.concat( subsubs.map{ |subset| subset + value } )
+    end
+  end
+
+end
+