Are there any languages with "lateral" assignment operators?

Are there any languages with "lateral" assignment operators?

I don't know a really good name for what I'm talking about, but, most
programming languages use a syntax for assignment statements something
like this:
(variable) (assignment operator) (expression)
And some have some special assignment operators, such as var1 += var2
which is equivalent tovar1 = var1 + var2.
My question is basically, is there any language that would treat += like
above, but also have an =+ operator so that var1 =+ var2 would be
equivalent to var2 = var2 + var1?
Essentially, are there programming languages with "mirrorable" assignment
operators, so that the variable on the right is what gets assignment a new
variable (as opposed to the one on the left)?
Edit:
I suppose a much better example of what I'm referring to would be a
language in which you can have both (variable) (assignment operator)
(expression) and (expression) (assignment operator) (variable) as valid
statements.