error[E0382]: use of moved value: `blk` --> $DIR/once-cant-call-twice-on-heap.rs:9:5 | LL | blk(); | --- value moved here LL | blk(); //~ ERROR use of moved value | ^^^ value used here after move | = note: move occurs because `blk` has type `F`, which does not implement the `Copy` trait error: aborting due to previous error For more information about this error, try `rustc --explain E0382`.