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+This error indicates that a lifetime is missing from a type. If it is an error
+inside a function signature, the problem may be with failing to adhere to the
+lifetime elision rules (see below).
+
+Erroneous code examples:
+
+```compile_fail,E0106
+struct Foo1 { x: &bool }
+              // ^ expected lifetime parameter
+struct Foo2<'a> { x: &'a bool } // correct
+
+struct Bar1 { x: Foo2 }
+              // ^^^^ expected lifetime parameter
+struct Bar2<'a> { x: Foo2<'a> } // correct
+
+enum Baz1 { A(u8), B(&bool), }
+                  // ^ expected lifetime parameter
+enum Baz2<'a> { A(u8), B(&'a bool), } // correct
+
+type MyStr1 = &str;
+           // ^ expected lifetime parameter
+type MyStr2<'a> = &'a str; // correct
+```
+
+Lifetime elision is a special, limited kind of inference for lifetimes in
+function signatures which allows you to leave out lifetimes in certain cases.
+For more background on lifetime elision see [the book][book-le].
+
+The lifetime elision rules require that any function signature with an elided
+output lifetime must either have:
+
+ - exactly one input lifetime
+ - or, multiple input lifetimes, but the function must also be a method with a
+   `&self` or `&mut self` receiver
+
+In the first case, the output lifetime is inferred to be the same as the unique
+input lifetime. In the second case, the lifetime is instead inferred to be the
+same as the lifetime on `&self` or `&mut self`.
+
+Here are some examples of elision errors:
+
+```compile_fail,E0106
+// error, no input lifetimes
+fn foo() -> &str { }
+
+// error, `x` and `y` have distinct lifetimes inferred
+fn bar(x: &str, y: &str) -> &str { }
+
+// error, `y`'s lifetime is inferred to be distinct from `x`'s
+fn baz<'a>(x: &'a str, y: &str) -> &str { }
+```
+
+[book-le]: https://doc.rust-lang.org/book/ch10-03-lifetime-syntax.html#lifetime-elision