     
     func test_replaceNil_whenInvokedWithNonNil_thenReturnsOriginalValue() {
         // given
-        let number: Int? = 3
-        
-        // when
-        let result = number.replaceNil(with: 2)
+        let nonNilledNumber: Int? = 3
+        
+        // when
+        let result = nonNilledNumber.replaceNil(with: 2)
         
         // then
         XCTAssertEqual(result, 3)

    
    func test_isNone_whenInvokedOnNonNilValue_thenReturnsFalse() {
        // given
        let number: Int? = 3
        
        // then
        XCTAssertFalse(number.isNone)
    }
    
    func test_isNone_whenInvokedOnNilValue_thenReturnsTrue() {

    
    func test_isSome_whenInvokedOnNonNilValue_thenReturnsTrue() {
        // given
        let nonNilledNumber: Int? = 3
        
        // then
        XCTAssertTrue(nonNilledNumber.isSome)
    }
    
    func test_isSome_whenInvokedOnNilValue_thenReturnsFalse() {
