Fix E0806: Closure Captures Variables Invalid for Current Function

Tue, 28 Jul 2026 07:56:04 +0800

1. Symptoms

When Rust encounters error E0806, you will see compilation failure with a message similar to the following:

error[E0806]: closure may outlive the current function, but it may only capture
variables that are valid for the current function
  --> src/main.rs:6:17
   |
6  |     let cl = || println!("captured: {}", captured);
   |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
7  |     cl();
8  | }
   |
note: closure captures `captured` which is referenced by this closure

The compiler indicates that the closure captures a variable that does not have a lifetime extending beyond the current function’s scope. In more complex scenarios with attempted return values, you might see additional notes:

E0806 on ErrorVault — Developer Error Code Dictionary

Fix E0806: Closure Captures Variables Invalid for Current Function

1. Symptoms