Created
February 5, 2017 18:39
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| use std::mem; | |
| #[derive(Debug)] | |
| pub struct SaveResult { | |
| sentinel: i64, | |
| dir: SaveDir, | |
| } | |
| #[derive(Debug)] | |
| pub enum SaveDir { | |
| Temp(String), | |
| Perm(String), | |
| } | |
| impl SaveDir { | |
| pub fn keep(&mut self) { | |
| use self::SaveDir::*; | |
| *self = match mem::replace(self, Perm(String::new())) { | |
| Temp(tempdir) => Perm(tempdir), | |
| old_self => old_self, | |
| }; | |
| } | |
| } | |
| fn main() { | |
| let x = test_case(); | |
| } | |
| fn test_case() -> SaveDir { | |
| // we create some enum ... | |
| let dir = SaveDir::Temp(String::from("foo")); | |
| // we need this foo_result "wrapper" because the ICE seems related to this | |
| // enum being partially moved out of a struct... | |
| let foo_result = SaveResult { sentinel: 42, dir: dir }; | |
| // we try to convert it to its "permanent" variant | |
| // this is not actually legal, foo_result needs to be a mutable binding | |
| // if you do `let mut foo_result = ...;` above this won't ICE (!!!) | |
| foo_result.dir.keep(); foo_result.dir | |
| } |
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