From 93e302ba98c67a77f9c7fdb108c7bcc384e3a30d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Per=20Nordl=C3=B6w?= <per.nordlow@gmail.com>
Date: Thu, 19 Jan 2017 00:16:20 +0100
Subject: [PATCH] Compacter definition of isSigned including extra unittests

---
 std/traits.d | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/std/traits.d b/std/traits.d
index 46472822f..38460314f 100644
--- a/std/traits.d
+++ b/std/traits.d
@@ -5429,10 +5429,16 @@ enum bool isUnsigned(T) = __traits(isUnsigned, T) && !(is(Unqual!T == char) ||
 /**
 Detect whether $(D T) is a built-in signed numeric type.
  */
-enum bool isSigned(T) = is(SignedTypeOf!T) && !isAggregateType!T;
+enum bool isSigned(T) = __traits(isArithmetic, T) && !__traits(isUnsigned, T);
 
 @safe unittest
 {
+    enum E { e1 = 0 }
+    static assert(isSigned!E);
+
+    enum Eubyte : ubyte { e1 = 0 }
+    static assert(!isSigned!Eubyte);
+
     foreach (T; TypeTuple!(SignedIntTypeList))
     {
         foreach (Q; TypeQualifierList)