Is evaluation order unspecified or left-to-right?

The Expressions page in the documentation says this for function application:

"The order in which these side-effects take place is undefined, except that all side-effects produced by one statement occur before its successor statement."

but then it says this for partial application:

"The evaluation of this expression first causes f and each vi to be evaluated, in order from left to right"

It doesn't actually specify the evaluation order for any other subexpressions (arrays, field replace, etc).

There should be a separate section on evaluation order to make it quite clear.