get-extent in editor<%>
Gets the current extent of the editor's graphical representation.
The result is only valid when the editor is displayed (see
Basic Organization).
For text% objects, calling this method may force the recalculation of location
information if a maximum width is set for the editor, even if the editor currently has delayed refreshing (see
refresh-delayed?).
(-> voidsendan-editorget-extentwh)
w: boxed non-negative real number or#f
h: boxed non-negative real number or#fThe
wbox is filled with the editor's width, unlesswis#f. Thehbox is filled with the editor's height, unlesshis#f.