add vendor

vendor/github.com/zclconf/go-cty/cty/set/rules.go

@@ -0,0 +1,47 @@
+package set
+
+// Rules represents the operations that define membership for a Set.
+//
+// Each Set has a Rules instance, whose methods must satisfy the interface
+// contracts given below for any value that will be added to the set.
+type Rules interface {
+	// Hash returns an int that somewhat-uniquely identifies the given value.
+	//
+	// A good hash function will minimize collisions for values that will be
+	// added to the set, though collisions *are* permitted. Collisions will
+	// simply reduce the efficiency of operations on the set.
+	Hash(interface{}) int
+
+	// Equivalent returns true if and only if the two values are considered
+	// equivalent for the sake of set membership. Two values that are
+	// equivalent cannot exist in the set at the same time, and if two
+	// equivalent values are added it is undefined which one will be
+	// returned when enumerating all of the set members.
+	//
+	// Two values that are equivalent *must* result in the same hash value,
+	// though it is *not* required that two values with the same hash value
+	// be equivalent.
+	Equivalent(interface{}, interface{}) bool
+
+	// SameRules returns true if the instance is equivalent to another Rules
+	// instance.
+	SameRules(Rules) bool
+}
+
+// OrderedRules is an extension of Rules that can apply a partial order to
+// element values. When a set's Rules implements OrderedRules an iterator
+// over the set will return items in the order described by the rules.
+//
+// If the given order is not a total order (that is, some pairs of non-equivalent
+// elements do not have a defined order) then the resulting iteration order
+// is undefined but consistent for a particular version of cty. The exact
+// order in that case is not part of the contract and is subject to change
+// between versions.
+type OrderedRules interface {
+	Rules
+
+	// Less returns true if and only if the first argument should sort before
+	// the second argument. If the second argument should sort before the first
+	// or if there is no defined order for the values, return false.
+	Less(interface{}, interface{}) bool
+}