After some debugging into a problem I was finding, I determined that TFPHashList.FindIndexOf only works of the Key has non-nil data associated with it. In other words:

list.Add('abcd', nil);
result := list.FindIndexOf('abcd');

In that case, result will be -1, because the InternalFind procedure only returns a value "if assigned(Data)".

I think this is wrong behavior, or at least it's documented wrong. The documentation says:

"FindIndexOf returns the index of the key AName, or -1 if the key does not exist in the list. It uses the hash value to search for the key."

Well, the key DOES exist in the list... it's just associated with nil data.

Should I log a bug? Or is this really how it's supposed to work?

-SG