         ///         and match any combination of its options.
         public func availableFontFeatures(includeIdentifiers includeIDs: Bool = false) -> String {
             let preamble = "Available font features of \(fontName)"
-            return preamble + availableFeaturesDictionaries.map { featureDict in
+            let features: [String] = availableFeaturesDictionaries.map { featureDict in
                 let featureName = featureDict[kCTFontFeatureTypeNameKey as String] as? String
                 let exclusive = featureDict[kCTFontFeatureTypeExclusiveKey as String] as? Bool ?? false
                 let selectors = featureDict[kCTFontFeatureTypeSelectorsKey as String] as? [FontFeatureDictionary] ?? []

                resultString += "\n    Exclusive: \(exclusive)"
                if !selectors.isEmpty {
                    resultString += "\n    Selectors:"
                    resultString += selectors.map { selectorDict in
                        let selectorName = selectorDict[kCTFontFeatureSelectorNameKey as String] as? String
                        let selectorIsDefault = selectorDict[kCTFontFeatureSelectorDefaultKey as String] as? Bool ?? false


                            resultString += " (default)"
                        }
                        return resultString
                    }
                    resultString += selectorStrings.reduce("") { $0 + "\n" + $1 }
                }
                return resultString
            }
            return preamble + features.reduce("") { $0 + "\n\n" + $1 }
        }

    }
