Toggling system variables

I am trying to set up some routines that will take a current variable (i.e.
osnaphatch) and toggle the current setting (i.e. 0 to 1 or 1 to 0). Could
you guys please give me a starting point.

Thanks as always
Mack

 

(setvar "osnaphatch"(boole 6 1(getvar "osnaphatch")))

Bill

 

In lisp:

(setvar "osnaphatch" (- 1 (getvar "osnaphatch")))

In diesel (for menus):

'osnaphatch $M=$(xor,$(getvar, osnaphatch),1)

 

Another possible approach:

(if (= (getvar "osnaphatch") 1) (setvar "osnaphatch" 0) (setvar "osnaphatch"
1))

Kent Cooper, AIA


...

 

I wondered about the acceptability of setting one of these 0 or 1 variables
to -1. (I'm on 2004, so I don't have OSNAPHATCH to check with, but I tried
it with SNAPMODE.) Two things:

1. While it does NOT accept typing in -1 as a value, it DOES accept Allen's
lisp approach (if it's currently zero, and you subtract one from it, somehow
it returns just plain 1, rather than -1). Does anyone know why?

2. In the case of SNAPMODE in particular, if you put that in as a "command"
or as an option in the SETVAR command, and try to enter -1, it says:

Requires an integer between 0 and 2.

Help does NOT mention 2 as a possible value, but you can, in fact, set it to
2. Does anyone know what it does? Help says 1 is "Snap on for the current
viewport", so might 2 be for "Snap on for all viewports"? Does 2005 Help
list 2 as a value?


Another thing: if you want a "toggle" to be more like a "cycle" for
something with more than just 0 and 1 values (apparently now SNAPMODE, but
also for example SNAPISOPAIR for the Isometric Plane), you can do something
[equivalent to F5] like:

(if (= (getvar "snapisopair") 2) (setvar "snapisopair" 0) (setvar
"snapisopair" (1+ (getvar "snapisopair"))))

For a variable with more than 0, 1 & 2 (if there are any that go up to 3 or
something), change that 2 to whatever the highest allowable value is. (You
COULD even do it for something that adds up power-of-two values, like
OSMODE, but that seems kind of silly.)

Kent Cooper, AIA


...

 

Command: (- 1 0)
1

Command: (- 1 1)
0

 

1 from my macro library:

(defun toggle (v)
(and (= (type v) 'STR)
(getvar v)
(or (= (getvar v) 0)
(= (getvar v) 1))
(setvar v (- 1 (getvar v))))
(getvar v))

-David

 

As Jason pointed out, I'm not subtracting one from the value, but rather the value FROM one.

 

But actually using the boole 6 function, as BillZ shows, is better, since boole 6 is the XOR
function.
I always forget about yhe boole functions!

 

I guess I was thinking of (- 1 ...) [with a space between the - and the 1]
as being the same as (-1 ...) [without the space] -- got the order of what
was being subtracted from what wrong.

But I'm still interested in what a SNAPMODE value of 2 means...

Kent Cooper, AIA


...
....

the value FROM one.

 

Help files from 2005 do not list a value of 2, FWIW.

 

Another possible approach:

"osnaphatch" 1))

Possible, but less elegant than previously posted solutions. A shorter
version of the same thing, avoiding the repetitive setvar, would be:

(setvar "osnaphatch" (if (= (getvar "osnaphatch") 1) 0 1))

There are any number of possible ways to get there, but I haven't seen any
more concise than the direct methods of using a boolean operation or
subtracting from 1.