diff options
Diffstat (limited to 'src/data')
| -rw-r--r-- | src/data/coarena.rs | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/src/data/coarena.rs b/src/data/coarena.rs index ac6e43f..549c5f2 100644 --- a/src/data/coarena.rs +++ b/src/data/coarena.rs @@ -21,6 +21,20 @@ impl<T> Coarena<T> { self.data.get(index as usize).map(|(_, t)| t) } + /// Deletes an element for the coarena and returns its value. + /// + /// We can't really remove an element from the coarena. So instead of actually removing + /// it, this method will reset the value to the given `removed_value`. + pub fn remove(&mut self, index: Index, removed_value: T) -> Option<T> { + let (i, g) = index.into_raw_parts(); + let data = self.data.get_mut(i as usize)?; + if g == data.0 { + Some(std::mem::replace(&mut data.1, removed_value)) + } else { + None + } + } + /// Gets a specific element from the coarena, if it exists. pub fn get(&self, index: Index) -> Option<&T> { let (i, g) = index.into_raw_parts(); @@ -51,6 +65,27 @@ impl<T> Coarena<T> { self.data[i1 as usize] = (g1, value); } + /// Ensure that the given element exists in thihs coarena, and return its mutable reference. + pub fn ensure_element_exist(&mut self, a: Index, default: T) -> &mut T + where + T: Clone, + { + let (i1, g1) = a.into_raw_parts(); + + if self.data.len() <= i1 as usize { + self.data + .resize(i1 as usize + 1, (u32::MAX, default.clone())); + } + + let data = &mut self.data[i1 as usize]; + + if data.0 != g1 { + *data = (g1, default); + } + + &mut data.1 + } + /// Ensure that elements at the two given indices exist in this coarena, and return their reference. /// /// Missing elements are created automatically and initialized with the `default` value. |