std-save-layer, std-restore-layer | ![]() |
These two complementing functions are used in error handling to save the state of a layer on init and restore the old state on restore.
STD-SAVE-LAYER returns a layer-state object for the given layer only. The return value may be used for std-restore-layer.
STD-RESTORE-LAYER takes the layer-state object which must be the layer-state object returned by std-save-layer and changes the layer properties of the specified layer according to this object. The layer-state object completely describes a LAYER entity. The layer might bepurged, created, turned on, off, frozen, thawed, locked, unlocked, changed it's color, aso.
Both functions are normally used by the error handling pair (STD-VAR-INIT '((:LAYER name))) and (STD-VAR-RESTORE) resp. (STD-VAR-PUSH alist) and (STD-VAR-POP), to restore the previous setting on user-breaks or errors.
(std-var-init '((:LAYER "ROOM"))) ... (command "'_LAYER" "_OFF" "ROOM" "")) ... (std-var-restore)
layer-state: a layer-state object, which might be a list.
STD-SAVE-LAYER returns a layer-state object.
The return value of STD-RESTORE-LAYER is undefined.
STD-RESTORE-LAYER may change the properties of the given layer.
(std-require 'STDTBL)
Defined in STDTBL