cznic / b Goto Github PK

Based on the doc:

Seek returns an Enumerator positioned on an item such that k >= item's key.

However, here's a test that appears to be a special case with item's key > k:

func TestSeekBeforeFirst(t *testing.T) {
	r := TreeNew(cmp)
	r.Set(42, 314)
	enum, ok := r.Seek(10)
	if ok {
		t.Fatal("WTF")
	}
	k, v, err := enum.Next()
	t.Logf("K: %v, V: %v, Err: %v", k, v, err)
}

Output:

=== RUN   TestSeekBeforeFirst
--- PASS: TestSeekBeforeFirst (0.00s)
	all_test.go:181: K: 42, V: 314, Err: <nil>

Would be nice to update the doc about this behavior or even better have nil, nil, io.EOF returned.

In order for this collection to provide an uniform api as part of the golang-collections project
i'm going to do the following.

Wrap Enumerator as a proper Nexter with a Next() method. This allows the user to walk the tree inorder.
implement Atter that stays near a certain key in the tree
Add an Atter .Fix() method that allows to synchronize the Atter after a collection insertions/deletions/rebalance.
Add method to MkNode() from an Atter. This allows O(1) insertion at any node in the structure
further things may be needed also but i'm really happy the enumerator is already implemented.

The fork is currently here:
https://github.com/golang-collections/b

Hey @cznic -- github.com/gordonklaus/ineffassign flagged this line as an ineffectual assignment:

I haven't examined this closely enough to figure out whether the line can just be deleted or whether it's a bug.

Hi, just a note to say thank you. I have more deeply profiled this lib vs. github.com/google/btree and found it superior. I have switched my more performance intensive use case already. I apologize for having to raise an issue to say this, however github.com has long ago disabled private messages. I also did not wish to continue the conversation on that repo, as it was becoming too unrelated to their library.

If i want to store btree in file and load/save it, how can i do that?