Previous/Last Continued

"LAST" is used in making selection sets to select the LAST entity created that is visible in the display area of the monitor.

"PREVIOUS" is similar to "LAST" except it selects the previous object(s) or, in other words, the previous selection set.

In addition to the basics listed above, there are many obscure little tricks to learn . . .

If, after hitting "Enter", you realize that there was an entity(s) that you should have REMOVED or ADDED (or even that you issued the wrong editing command) -- just cancel the command and then hit "Enter" again to repeat (or enter a new command) your editing command and "Previous". This will have reselected the Previous selection set and you will be able to ADD or REMOVE entities as required.

Most importantly and, possibly, the least obvious is "REMOVE-Previous". For example: MOVE some entities (this is selection set 'A') on top of several (hundreds?) other entities. Again, using the MOVE command, use a window to select selection set 'A' and the other entities, then issue -- "REMOVE-Previous". This will remove what you had originally moved (selection set 'A' ), not everything that you just selected! This is because a selection set does not become a "Previous" selection set until the current command is finished!

Editing with GRIPS does not result in a Previous Selection set, the Former-Previous Selection set is in affect.

• Points to Remember

• A "Previous" after using MATCHPROP does not include the Source Object, unless you specifically include it while making the Selection set that will be MATCHPROP'ed.
• BHATCH does not result in a Previous Selection set, the Former-Previous Selection set is in affect. However using the old HATCH command does create a new Selection set.
• The DDEDIT command does not result in a Previous Selection set, the Former-Previous Selection set is in affect, yet other dialogue commands do create a new Selection set!
• MPEDIT: has very interesting characteristics. MPEDIT creates a Selection set -- but only of the entities that are already PLINES and only if you answer "Yes" to the question "Convert lines and arcs to plines?". In other words, LINES and ARCS that are changed into PLINES by the command MPEDIT are not part of the new Selection set!
• MIRROR: If you answer "Yes" to the question "Delete original objects?" in the MIRROR command the newly mirrored entities will be selected by "Previous".
• WBLOCK: When WBLOCKing entities a "Previous" (after OOPSing the entities back) will reselect them. This will enable you to easily ADD or REMOVE entities as required to redefine the DWG file you have just created.
• "Cannot re-enter AutoLISP": This error message after issuing the SSX command requires the use of "Previous" in order to do a "work around". Use SSX to select objects and then issue a LISP routine command NAME, using "Previous" to select what was selected by SSX. You may now revise the Selection set using ADD and REMOVE.

As you can see the permutations are almost endless, however the main thing to remember is that you must be aware of how AutoCAD^® actually works! Only in this way will you avoid random lines, arcs, text etc. appearing all over what should be a pristine CAD drawing.

NOTE: Because of variations in computer setups, AutoCAD^® releases etc. please do not assume that all of these tips will apply to your specific situation.

Eric Bailey