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+This error indicates that the struct, enum or enum variant must be matched
+non-exhaustively as it has been marked as `non_exhaustive`.
+
+When applied within a crate, downstream users of the crate will need to use the
+`_` pattern when matching enums and use the `..` pattern when matching structs.
+Downstream crates cannot match against non-exhaustive enum variants.
+
+For example, in the below example, since the enum is marked as
+`non_exhaustive`, it is required that downstream crates match non-exhaustively
+on it.
+
+```rust,ignore (pseudo-Rust)
+#[non_exhaustive]
+pub enum Error {
+    Message(String),
+    Other,
+}
+
+impl Display for Error {
+    fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+        // This will not error, despite being marked as non_exhaustive, as this
+        // enum is defined within the current crate, it can be matched
+        // exhaustively.
+        let display = match self {
+            Message(s) => s,
+            Other => "other or unknown error",
+        };
+        formatter.write_str(display)
+    }
+}
+```
+
+An example of matching non-exhaustively on the above enum is provided below:
+
+```rust,ignore (pseudo-Rust)
+use mycrate::Error;
+
+// This will not error as the non_exhaustive Error enum has been matched with a
+// wildcard.
+match error {
+    Message(s) => ...,
+    Other => ...,
+    _ => ...,
+}
+```
+
+Similarly, for structs, match with `..` to avoid this error.