RE: Multiple assignments to the same variable

["Alexander Altshuler" <alt@...>]

On Tue, Jul 13, 2010 at 12:54 AM, Alexander Altshuler <alt@kaluga.ru>
wrote:
>>I stumbled accross something I couldn't find an anwer to in the Lua
>>manual. How is the bahavior of multiple assignments to the same
>>variable defined, e.g.
>>a,a = 1,2
>>or
>>t[1],t[1] = 1,2
> >From tests, it seems like the values are assigned from right to left,
>>overwriting the previous values (so a and t[1] is 1). However, since
>>this is not described in the manuals, I fear that this behavior might
>>not be stable. Or maybe someone can hint me where this behavior is
>>described if I overlooked it.
>
> http://www.lua.org/manual/5.1/manual.html#2.4.3
>
>

>I'm not sure where that defines how the statement is evaluated when
>the same variable appears twice on the left side of the assignment.

Yes, you are right, was not thinking.
Bytecodes listing shows right to left assignment.
Reference does not define the expression evaluation order and assignment
order.
But we always have workaround - single assigment.

Alexander