;*****************************************************************
;*    FILE:           FL.lsp                                     * 
;*    DESCRIPTION:    Isolates a layer by selecting an           *
;*                    entity on the layer to be isolated.        * 
;*    LAST UPDATED:   2-5-93                                     *
;*    USAGE:          Sets a layer current and freezes all other *
;*                    layers.                                    *  
;*    VARIABLES:      EXP Existing setting of variable "EXPERT". *
;*                    ENT Selected entity's name.                *
;*                    DDE Definition data of selected entity.    *
;*                    NAM Layer name of selected entity.         *
;*                                                               *
;*                                                               *
;*                                                               *
;*****************************************************************
       
       
             
(defun C:FL (/ EXP ENT DDE NAM)           ;Defines function
       (setq EXP (getvar "EXPERT"))         ;Sets value of Expert to EXP
       (setvar "expert" 1)                  ;Sets value of expert to 1 to
                                            ;supress prompts
       (setq ENT (car (ENTSEL "Select object on layer to isolate:")))
                                            ;Sets ENT to the entity name  of
                                            ;the selected object
       (setq DDE (entget ENT))              ;Sets DDE to the definition data of
                                            ;the selected entity 
       (setq NAM (cdr (assoc 8 DDE)))       ;Extracts the layer name from the
                                            ;definition data
   (command "LAYER" "S" NAM "FREEZE" "*" "THAW" NAM "")
                                            ;Issues the layer command, sets the
                                            ;entity layer current, and freezes all   
                                            ;other layers.
       (setvar "EXPERT" EXP)                ;Returns expert to previous value
   (PRINC)                                  ;Cleans command line
)                                           ;Closing parenthesis of routine