can-select? (augmentable only) in pasteboard%

This method is called before a snip in the pasteboard is selected or deselected. If #f is returned, the selection change is disallowed. This method is not called when a selected snip is to be deleted (and thus de-selected indirectly); see also can-delete? .

See also on-select and after-select.

The editor is internally locked for writing when this method is called (see also Locks).

• (send a-pasteboard can-select? snip on?) -> boolean
     snip : snip% object
     on? : boolean

  If on? is #t, then snip will be selected, otherwise snip will be deselected.