`rustc --explain E0507` prints a message which apparently discusses "error[E0507]: cannot move out of borrowed content": > You tried to move out of a value which was borrowed. ... (That's funny, because the error said I tried to "move out of captured outer variable in an `Fn` closure".) * If "cannot move out of captured outer variable in an `Fn` closure" really _is_ the same error, **this should be explained in the `--explain` text.** * If it is _not_ the same error, it should have its own error code and explanation.