vendor/hashbrown/src/scopeguard.rs

   1 // Extracted from the scopeguard crate
   2 use core::ops::{Deref, DerefMut};
   3
   4 pub struct ScopeGuard<T, F>
   5 where
   6     F: FnMut(&mut T),
   7 {
   8     dropfn: F,
   9     value: T,
  10 }
  11
  12 #[cfg_attr(feature = "inline-more", inline)]
  13 pub fn guard<T, F>(value: T, dropfn: F) -> ScopeGuard<T, F>
  14 where
  15     F: FnMut(&mut T),
  16 {
  17     ScopeGuard { dropfn, value }
  18 }
  19
  20 impl<T, F> Deref for ScopeGuard<T, F>
  21 where
  22     F: FnMut(&mut T),
  23 {
  24     type Target = T;
  25     #[cfg_attr(feature = "inline-more", inline)]
  26     fn deref(&self) -> &T {
  27         &self.value
  28     }
  29 }
  30
  31 impl<T, F> DerefMut for ScopeGuard<T, F>
  32 where
  33     F: FnMut(&mut T),
  34 {
  35     #[cfg_attr(feature = "inline-more", inline)]
  36     fn deref_mut(&mut self) -> &mut T {
  37         &mut self.value
  38     }
  39 }
  40
  41 impl<T, F> Drop for ScopeGuard<T, F>
  42 where
  43     F: FnMut(&mut T),
  44 {
  45     #[cfg_attr(feature = "inline-more", inline)]
  46     fn drop(&mut self) {
  47         (self.dropfn)(&mut self.value)
  48     }
  49 }