The function drop-object-provides-format
returns non-nil if the dropping operation can provide an object in the given format. It returns nil
if it cannot provide that format.
See set-drop-object-supported-formats for information on format keywords.
drop-object-provides-format
should only be called within a
drop-callback
. It is not supported on X11/Motif. See simple-pane for information about drop callbacks.
CAPI User Guide and Reference Manual (Macintosh version) - 3 Aug 2017