View difference between Paste ID: 3ETPsEsT and DxrTzZhe

 struct S(T) {
   T[] data;
 
-  int opApply(int delegate (ref T) dg) {
+  int opApply(int delegate (T*) dg) {
     for(size_t i = 0; i < data.length; i++) {
-      int result = dg(data[i]);
+      int result = dg(&data[i]);
       if(result != 0)
         return result;
     }
 
     return 0;
   }
 
-  int opApply(int delegate (const ref T) dg) const {
+  int opApply(int delegate (const T*) dg) const {
     for(size_t i = 0; i < data.length; i++) {
-      int result = dg(data[i]);
+      int result = dg(&data[i]);
       if(result != 0)
         return result;
     }
 
     return 0;
   }
 
-  int opApply(int delegate (size_t, ref T) dg) {
+  int opApply(int delegate (size_t, T*) dg) {
     for(size_t i = 0; i < data.length; i++) {
-      int result = dg(i, data[i]);
+      int result = dg(i, &data[i]);
       if(result != 0)
         return result;
     }
 
     return 0;
   }
 
-  int opApply(int delegate (size_t, const ref T) dg) const {
+  int opApply(int delegate (size_t, const T*) dg) const {
     for(size_t i = 0; i < data.length; i++) {
-      int result = dg(i, data[i]);
+      int result = dg(i, &data[i]);
       if(result != 0)
         return result;
     }
 
     return 0;
   }
 }
 
 void main() {
   auto s1 = S!int([0, 1, 2, 3]);
   auto s2 = const S!int([0, 1, 2, 3]);
 
   import std.stdio : writeln, writefln;
   writeln("S!int, 1 arg:");
   foreach(s; s1)
-    writeln(s);
+    (*s)++;
 
   writeln("S!int, 2 args:");
   foreach(i, s; s1)
-    writefln("%s: %s", i, s);
+    writefln("%s: %s", i, *s);
 
   writeln("const S!int, 1 arg:");
   foreach(s; s2)
-    writeln(s);
+    writeln(*s);
 
   writeln("const S!int, 2 args:");
   foreach(i, s; s2)
-    writefln("%s: %s", i, s);
+    writefln("%s: %s", i, *s);
 }