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sorted-btree

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A sorted list of key-value pairs in a fast, typed in-memory B+ tree with a powerful API.

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import BTree from '../b+tree'; /** * Returns a new tree containing only keys present in both input trees. * Neither tree is modified. * * Complexity is O(N + M) in the fully overlapping case and additionally bounded by O(log(N + M) * D), * where `D` is the number of disjoint key ranges, because disjoint subtrees are skipped entirely. * In practice, that means for keys of random distribution the performance is linear and for keys with significant * numbers of non-overlapping key ranges it is much faster. * @param treeA First tree to intersect. * @param treeB Second tree to intersect. * @param combineFn Called for keys that appear in both trees. Return the desired value. * @returns A new tree populated with the intersection. * @throws Error if the trees were created with different comparators. */ export default function intersect<TBTree extends BTree<K, V>, K, V>(treeA: TBTree, treeB: TBTree, combineFn: (key: K, leftValue: V, rightValue: V) => V): TBTree;