diff --git a/Hue.xcodeproj/project.pbxproj b/Hue.xcodeproj/project.pbxproj
index 55efff0..24a4a43 100644
--- a/Hue.xcodeproj/project.pbxproj
+++ b/Hue.xcodeproj/project.pbxproj
@@ -384,11 +384,11 @@
 					};
 					D52862111C3EAC1D00AD11AD = {
 						CreatedOnToolsVersion = 7.2;
-						LastSwiftMigration = 0800;
+						LastSwiftMigration = 1000;
 					};
 					D528621B1C3EAC1D00AD11AD = {
 						CreatedOnToolsVersion = 7.2;
-						LastSwiftMigration = 0800;
+						LastSwiftMigration = 1000;
 					};
 				};
 			};
@@ -807,6 +807,7 @@
 				PRODUCT_BUNDLE_IDENTIFIER = no.hyper.Hue;
 				PRODUCT_NAME = Hue;
 				SKIP_INSTALL = YES;
+				SWIFT_VERSION = 4.2;
 			};
 			name = Debug;
 		};
@@ -827,6 +828,7 @@
 				PRODUCT_NAME = Hue;
 				SKIP_INSTALL = YES;
 				SWIFT_OPTIMIZATION_LEVEL = "-Owholemodule";
+				SWIFT_VERSION = 4.2;
 			};
 			name = Release;
 		};
@@ -837,6 +839,7 @@
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks @loader_path/Frameworks";
 				PRODUCT_BUNDLE_IDENTIFIER = no.hyper.HueTests;
 				PRODUCT_NAME = "$(TARGET_NAME)";
+				SWIFT_VERSION = 4.2;
 			};
 			name = Debug;
 		};
@@ -848,6 +851,7 @@
 				PRODUCT_BUNDLE_IDENTIFIER = no.hyper.HueTests;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SWIFT_OPTIMIZATION_LEVEL = "-Owholemodule";
+				SWIFT_VERSION = 4.2;
 			};
 			name = Release;
 		};
diff --git a/Source/iOS/UIColor+Hue.swift b/Source/iOS/UIColor+Hue.swift
index dcf36bd..84cfc00 100644
--- a/Source/iOS/UIColor+Hue.swift
+++ b/Source/iOS/UIColor+Hue.swift
@@ -95,9 +95,9 @@ public extension UIColor {
     let threshold: CGFloat = 0.25
     var result = false
     
-    if fabs(bg[0] - fg[0]) > threshold || fabs(bg[1] - fg[1]) > threshold || fabs(bg[2] - fg[2]) > threshold {
-      if fabs(bg[0] - bg[1]) < 0.03 && fabs(bg[0] - bg[2]) < 0.03 {
-        if fabs(fg[0] - fg[1]) < 0.03 && fabs(fg[0] - fg[2]) < 0.03 {
+    if abs(bg[0] - fg[0]) > threshold || abs(bg[1] - fg[1]) > threshold || abs(bg[2] - fg[2]) > threshold {
+      if abs(bg[0] - bg[1]) < 0.03 && abs(bg[0] - bg[2]) < 0.03 {
+        if abs(fg[0] - fg[1]) < 0.03 && abs(fg[0] - fg[2]) < 0.03 {
           result = false
         }
       }