     
     override func tearDown() {
         super.tearDown()
+    }
+    
+    func testThatConstantCreatedWithEqualPrefixCreatesTheExpectedProperties() {
+        // given
+        // when
+        let constant = (==350)
+        
+        // then
+        XCTAssertTrue(constant.value == 350)
+        XCTAssertTrue(constant.relation == .Equal)
     }
     
     func testThatConstantCreatedWithGreaterThanPrefixCreatesTheExpectedProperties() {

        let lessThan = (<=200)
        let multipliedBy = (*200)
        let equalTo = Constant(value: 200, relation: .Equal, multiplier: 1.0)
        
        // when
        let greaterThanMultiplier = greaterThan.multiplier
        let lessThanMultiplier = lessThan.multiplier
        let multipliedByMultiplier = multipliedBy.multiplier
        let equalToMultiplier = equalTo.multiplier
        
        // then
        XCTAssertTrue(greaterThanMultiplier == 1.0)
        XCTAssertTrue(lessThanMultiplier == 1.0)
        XCTAssertTrue(multipliedByMultiplier == 200.0)
        XCTAssertTrue(equalToMultiplier == 1.0)
    }
    
    func testThatLayoutValueIsTheExpected() {

        let lessThan = (<=200)
        let multipliedBy = (*200)
        let equalTo = Constant(value: 200, relation: .Equal, multiplier: 1.0)
        let equalToPref = (==200)
        
        // when
        let greaterThanRelation = greaterThan.relation
        let lessThanRelation = lessThan.relation
        let multipliedByRelation = multipliedBy.relation
        let equalToRelation = equalTo.relation
        let equalToPrefRelation = equalToPref.relation
        
        // then
        XCTAssertTrue(greaterThanRelation == .GreaterThanOrEqual)
        XCTAssertTrue(lessThanRelation == .LessThanOrEqual)
        XCTAssertTrue(multipliedByRelation == .Equal)
        XCTAssertTrue(equalToRelation == .Equal)
        XCTAssertTrue(equalToPrefRelation == .Equal)
    }
    
    func testThatLayoutMultiplierIsTheExpected() {
