Callbacks.has() documentation should describe the signature with no parameters

[terrabruder]

Callbacks.has() (without parameters) returns true if the object has listeners and false otherwise. There are a few reasons that this behavior should be explicitly documented:

• The general knowledge of the presence of listeners as frequently useful (in the creation of default behavior, for example)
• This signature is far more performant than the search for a specific listener
• State knowledge is more consistent with loose coupling than specific knowledge

Please add documentation for this signature.

Examples might include a demonstration of this behavior before and after the use of the Callbacks.add and Callbacks.remove methods.

[bradleyayers]

Please also note that this "enhancement" was added in 1.9.1.

[arthurvr]

Assigned this to me, will take it this evening.

[terrabruder]

Thanks!

[arthurvr]

Looks like it's already done. That page already specifies the callback parameter is optional and has this in its <desc>:

Determine whether or not the list has any callbacks attached.

[arthurvr]

Oh I've got it, 6f40df9 fixed this but somebody forgot to close this issue.

[kswedberg]

My mistake. Sorry about that, @arthurvr .