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+A value was moved out while it was still borrowed.
+
+Erroneous code example:
+
+```compile_fail,E0505
+struct Value {}
+
+fn borrow(val: &Value) {}
+
+fn eat(val: Value) {}
+
+fn main() {
+    let x = Value{};
+    let _ref_to_val: &Value = &x;
+    eat(x);
+    borrow(_ref_to_val);
+}
+```
+
+Here, the function `eat` takes ownership of `x`. However,
+`x` cannot be moved because the borrow to `_ref_to_val`
+needs to last till the function `borrow`.
+To fix that you can do a few different things:
+
+* Try to avoid moving the variable.
+* Release borrow before move.
+* Implement the `Copy` trait on the type.
+
+Examples:
+
+```
+struct Value {}
+
+fn borrow(val: &Value) {}
+
+fn eat(val: &Value) {}
+
+fn main() {
+    let x = Value{};
+
+    let ref_to_val: &Value = &x;
+    eat(&x); // pass by reference, if it's possible
+    borrow(ref_to_val);
+}
+```
+
+Or:
+
+```
+struct Value {}
+
+fn borrow(val: &Value) {}
+
+fn eat(val: Value) {}
+
+fn main() {
+    let x = Value{};
+
+    let ref_to_val: &Value = &x;
+    borrow(ref_to_val);
+    // ref_to_val is no longer used.
+    eat(x);
+}
+```
+
+Or:
+
+```
+#[derive(Clone, Copy)] // implement Copy trait
+struct Value {}
+
+fn borrow(val: &Value) {}
+
+fn eat(val: Value) {}
+
+fn main() {
+    let x = Value{};
+    let ref_to_val: &Value = &x;
+    eat(x); // it will be copied here.
+    borrow(ref_to_val);
+}
+```
+
+For more information on Rust's ownership system, take a look at the
+[References & Borrowing][references-and-borrowing] section of the Book.
+
+[references-and-borrowing]: https://doc.rust-lang.org/book/ch04-02-references-and-borrowing.html