can-delete? (augmentable only) in pasteboard%
Called before a snip is deleted from the editor.
If the return value is #f, then the
delete will be aborted.
See also
on-delete and
after-delete.
The editor is internally locked for writing when this method is called (see also Locks).
(-> booleansenda-pasteboardcan-delete?snip)
snip:snip%object