From 6d016806857bc5d4c129c9c0862088d930c107a2 Mon Sep 17 00:00:00 2001
From: Eugen Wissner <belka@caraus.de>
Date: Mon, 8 Oct 2018 17:51:59 +0200
Subject: [PATCH] conv.emplace: Fix emplacing structs w/o this()

---
 source/tanya/container/array.d |  2 +-
 source/tanya/conv.d            | 21 +++++++++++++++++++--
 2 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/source/tanya/container/array.d b/source/tanya/container/array.d
index 2501fad..f8c1032 100644
--- a/source/tanya/container/array.d
+++ b/source/tanya/container/array.d
@@ -1587,7 +1587,7 @@ struct Array(T)
 
 @nogc nothrow pure @safe unittest
 {
-    struct SWithDtor
+    static struct SWithDtor
     {
         ~this() @nogc nothrow pure @safe
         {
diff --git a/source/tanya/conv.d b/source/tanya/conv.d
index 8eeb250..57580ff 100644
--- a/source/tanya/conv.d
+++ b/source/tanya/conv.d
@@ -190,13 +190,17 @@ do
         static assert(is(typeof({ static T t; })),
                       "Default constructor is disabled");
     }
+    else static if (is(typeof(result.__ctor(args))))
+    {
+        result.__ctor(args);
+    }
     else static if (is(typeof(T(args))))
     {
         *result = T(args);
     }
-    else static if (is(typeof(result.__ctor(args))))
+    else static if (is(typeof(*result = args))) // Args.length == 1, assignment
     {
-        result.__ctor(args);
+        *result = args;
     }
     else
     {
@@ -245,6 +249,19 @@ do
     static assert(is(typeof(emplace!F((void[]).init))));
 }
 
+// Can emplace structs without a constructor
+@nogc nothrow pure @safe unittest
+{
+    static struct SWithDtor
+    {
+        ~this() @nogc nothrow pure @safe
+        {
+        }
+    }
+    static assert(is(typeof(emplace!SWithDtor(null, SWithDtor()))));
+    static assert(is(typeof(emplace!SWithDtor(null))));
+}
+
 /**
  * Thrown if a type conversion fails.
  */