Merge pull request #149 from dn-m/newtype

Add Comparable conformance to NewType

Author: jsbean

Sources/DataStructures/NewType.swift

@@ -17,6 +17,12 @@ extension NewType {
     }
 }
 
+extension NewType where Value: Comparable {
+    public static func < (lhs: Self, rhs: Self) -> Bool {
+        return lhs.value < rhs.value
+    }
+}
+
 extension NewType where Value: ExpressibleByIntegerLiteral {
     public init(integerLiteral value: Value.IntegerLiteralType) {
         self.init(value: Value(integerLiteral: value))

Tests/DataStructuresTests/NewTypeTests.swift

@@ -10,6 +10,14 @@ import DataStructures
 
 class NewTypeTests: XCTestCase {
 
+    func testComparable() {
+        struct C: NewType, Comparable { let value: Int }
+        let a = C(1)
+        let c = C(2)
+        XCTAssert(a < c)
+        XCTAssert(c > a)
+    }
+
     func testExpressibleByIntegerLiteral() {
         struct I: NewType, ExpressibleByIntegerLiteral { let value: Int }
         let _: I = 42