Update struct.dd

Author: andralex

spec/struct.dd

@@ -835,7 +835,7 @@ void main()
         are generated without any implicit qualifiers and are not considered
         struct members. This leads to the situation where qualifying an
         entire struct declaration does not have any impact on the above
-        mentioned postblits, however, since `__xpostblit` is a member of
+        mentioned postblits. However, since `__xpostblit` is a member of
         the struct and an alias of one of the other postblits, the qualifiers
         applied to the struct will affect the aliased postblit:)
 
@@ -846,8 +846,8 @@ struct S
     { }
 }
 
-// `__xpostblit` aliases the aggregated postblit so the `const` applies to it,
-// however, the aggregated postblit calls the field postblit which does not have
+// `__xpostblit` aliases the aggregated postblit so the `const` applies to it.
+// However, the aggregated postblit calls the field postblit which does not have
 // any qualifier applied, resulting in a qualifier mismatch error
 const struct B
 {
@@ -862,20 +862,21 @@ const struct B2
     S a;
 }
 
-// ditto B
+// Similar to B
 immutable struct C
 {
     S a;        // error : mutable method C.__fieldPostblit is not callable using a immutable object
     this(this)
     { }
 }
 
+// Similar to B2, compiles
 immutable struct C2
 {
     S a;
 }
 
-// ditto B
+// Similar to B
 shared struct D
 {
     // error: non-shared method S.__postblit is not callable using a shared object
@@ -884,9 +885,16 @@ shared struct D
     this(this)
     { }
 }
+
+// Unlike B2, this example also does not work due to additional restrictions on shared.
+shared struct D2
+{
+    // error: non-shared method S.__postblit is not callable using a shared object
+    S a;
+}
 ---
 
-        $(P In the above situations the errors do not contain any line numbers because
+        $(P In the above situations the errors do not contain line numbers because
         the errors are regarding generated code. In the case of the `shared` struct,
         the first error message can be suppressed by qualifying the postblit of `S`
         with `shared`.