I was going to say Perl always evaluates operands in left to right order, but it's not the case.

It does, unless precedence or associativity gets in your way. Your example demonstrates this quite well: 

var() = foo() + bar() * baz();
  6       1       2       3
      7       5       4

Precedence
tightest:   *
            +
loosest:    =

[download]

So the arguments are evaluated left-to-right on the LHS of the =, then the sub expressions in order of their precedence, then the RHS. (perltrap documents that the RHS is evaluated first, btw).

Update: the more I think about this, the less sure I am. So try not rely too much on it ;-)

In short, you might be able to rely on the order in which operands are evaluated, but I consider it a bad practice

Fully agreed.

Second update

Ok, the operands are evaluated left-to-right, the operators according to their precedence/associativity.

The assignment operator is an exception (on which we rely quite often).

In reply to Re^2: Will "$_[0]=shift" always resolve shift first? by moritz
in thread Will "$_[0]=shift" always resolve shift first? by kyle

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