Fix #57

src/dfmt.d

@@ -382,6 +382,11 @@ private:
             case tok!"~":
                 if (peekIs(tok!"this"))
                 {
+                    if (!(index == 0 || peekBackIs(tok!"{") || peekBackIs(tok!"}")
+                        || peekBackIs(tok!";")))
+                    {
+                        write(" ");
+                    }
                     writeToken();
                     break;
                 }

tests/issue0057.d

@@ -0,0 +1,12 @@
+	~this()
+{
+}
+
+extern(C++)~this()
+{	global.gag = oldgag;
+}
+
+struct S
+{public~this()
+	{
+	}}

tests/issue0057.d.ref

@@ -0,0 +1,15 @@
+~this()
+{
+}
+
+extern (C++) ~this()
+{
+    global.gag = oldgag;
+}
+
+struct S
+{
+    public ~this()
+    {
+    }
+}