use Fence to avoid conflict between alias fmt and string file

funkwerk-mobility · May 30, 2018 · 640a8c2 · 640a8c2
1 parent c7d3835
commit 640a8c2
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Showing 2 changed files with 9 additions and 4 deletions.
diff --git a/example.d b/example.d
@@ -8,7 +8,7 @@ import util.log;
 
 string details()
 {
-    import std.stdio;
+    import std.stdio : writeln;
 
     writeln("lazy evaluation");
     return "details";

diff --git a/src/util/log.d b/src/util/log.d
@@ -108,24 +108,29 @@ struct Log
     alias error = append!(LogLevel.error);
     alias fatal = append!(LogLevel.fatal);
 
+    private struct Fence {}  // argument cannot be provided explicitly
+
     template append(LogLevel level)
     {
-        void append(alias fmt, size_t line = __LINE__, string file = __FILE__, A...)(lazy A args)
+        void append(alias fmt, Fence _ = Fence(), string file = __FILE__, size_t line = __LINE__, A...)
+            (lazy A args)
         if (isSomeString!(typeof(fmt)))
         {
             static if (!level.disabled)
                 if (level & levels)
                     _append(level, file, line, format!fmt(args));
         }
 
-        void append(size_t line = __LINE__, string file = __FILE__, Char, A...)(in Char[] fmt, lazy A args)
+        void append(Fence _ = Fence(), string file = __FILE__, size_t line = __LINE__, Char, A...)
+            (in Char[] fmt, lazy A args)
         {
             static if (!level.disabled)
                 if (level & levels)
                     _append(level, file, line, format(fmt, args));
         }
 
-        void append(size_t line = __LINE__, string file = __FILE__, A)(lazy A arg)
+        void append(Fence _ = Fence(), string file = __FILE__, size_t line = __LINE__, A)
+            (lazy A arg)
         {
             static if (!level.disabled)
                 if (level & levels)