| Sky Base |
| ======== |
| |
| AbstractNode |
| ------------ |
| |
| The [node.dart](node.dart) file defines a class, `AbstractNode`, which |
| can be used to build mutable trees. |
| |
| * When a subclass is changing the parent of a child, it should |
| call either parent.adoptChild(child) or parent.dropChild(child) |
| as appropriate. Subclasses should expose an API for |
| manipulating the tree if you want to (e.g. a setter for a |
| 'child' property, or an 'add()' method to manipulate a list). |
| |
| * You can see the current parent by querying 'parent'. |
| |
| * You can see the current attachment state by querying |
| 'attached'. The root of any tree that is to be considered |
| attached should be manually attached by calling 'attach()'. |
| Other than that, don't call 'attach()' or 'detach()'. This is |
| all managed automatically assuming you call the 'adoptChild()' |
| and 'dropChild()' methods appropriately. |
| |
| * Subclasses that have children must override 'attach()' and |
| 'detach()' as described below. |
| |
| * Nodes always have a 'depth' greater than their ancestors'. |
| There's no guarantee regarding depth between siblings. The |
| depth of a node is used to ensure that nodes are processed in |
| depth order. The 'depth' of a child can be more than one |
| greater than the 'depth' of the parent, because the 'depth' |
| values are never decreased: all that matters is that it's |
| greater than the parent. Consider a tree with a root node A, a |
| child B, and a grandchild C. Initially, A will have 'depth' 0, |
| B 'depth' 1, and C 'depth' 2. If C is moved to be a child of A, |
| sibling of B, then the numbers won't change. C's 'depth' will |
| still be 2. This is all managed automatically assuming you call |
| 'adoptChild()' and 'dropChild()' appropriately. |
| |
| |
| Dependencies |
| ------------ |
| |
| No dependencies except for `dart:sky` and Dart's core libraries. |
