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diff --git a/compiler/rustc_error_codes/src/error_codes/E0531.md b/compiler/rustc_error_codes/src/error_codes/E0531.md
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+An unknown tuple struct/variant has been used.
+
+Erroneous code example:
+
+```compile_fail,E0531
+let Type(x) = Type(12); // error!
+match Bar(12) {
+    Bar(x) => {} // error!
+    _ => {}
+}
+```
+
+In most cases, it's either a forgotten import or a typo. However, let's look at
+how you can have such a type:
+
+```edition2018
+struct Type(u32); // this is a tuple struct
+
+enum Foo {
+    Bar(u32), // this is a tuple variant
+}
+
+use Foo::*; // To use Foo's variant directly, we need to import them in
+            // the scope.
+```
+
+Either way, it should work fine with our previous code:
+
+```edition2018
+struct Type(u32);
+
+enum Foo {
+    Bar(u32),
+}
+use Foo::*;
+
+let Type(x) = Type(12); // ok!
+match Type(12) {
+    Type(x) => {} // ok!
+    _ => {}
+}
+```