instanceof-subject and instanceof-type-designator cannot be expression

[Hywan]

If I read the grammar correctly, instanceof is defined as follow:

instanceof-expression:
   unary-expression
   instanceof-subject   instanceof   instanceof-type-designator

instanceof-subject:
   expression

instanceof-type-designator:
   qualified-name
   expression

But expression is defined as:

expression:
   yield-expression
   include-expression
   include-once-expression
   require-expression
   require-once-expression

So it does not make sense. Maybe instace of expression we should use primary-expression (but even not really) or assignment (or thinner):

  instanceof-subject:
-    expression
+    assignment

  instanceof-type-designator:
     qualified-name
-    expression
+    assignement

Thoughts?

[nikic]

There is no assignment production, did you mean variable? That would be better than what we have right now, though it's not entirely correct. The RHS of instanceof is a "new variable", which is a slightly restricted form of "variable", which is currently not the grammar :/

[mattacosta]

If I remember PHP's grammar correctly, "new variable" was actually very restricted. To the point where it is basically just something like:

instanceof-type-designator:
  qualified-name
  new-variable

new-variable
  simple-variable
  qualified-name :: simple-variable
  new-variable [ expression<sub>opt</sub> ]
  new-variable { expression }
  new-variable -> member-name
  new-variable :: simple-variable

[Hywan]

It sounds a little bit complicated… The PHP grammar has so much different nodes…