[18][guarded pattern] conditional-and query - spec clarification

[Manoj Palat]

Hi,

Given,
      public void bar(Object o) {
      int i = switch(o) {
            case String a && o != null ? true : false -> 1;//ecj flags syntax error here
            default -> 1;
      };
    }

ECJ(eclipse compiler for Java) flags a syntax error on the guarded pattern. However, javac accepts.

Ecj translates this into:
case ((String a) && (o != null)) ? true : false
and flags an error instead of
case ((String a) && ((o != null) ? true : false))

And I think the ecj is correct in flagging the error due to:

From https://docs.oracle.com/javase/tutorial/java/nutsandbolts/operators.html we see that  Conditional-And Operator “&&”  has higher operator precedence than the Conditional Operator “?:” . From https://docs.oracle.com/javase/specs/jls/se17/html/jls-15.html#jls-15.23, we see that “The conditional-and operator is syntactically left-associative (it groups left-to-right).”


Also, I don't see any mention of the precedence changes in spec 420 [latest at https://cr.openjdk.java.net/~gbierman/jep420/latest]

A more detailed reasoning (the above cut verbatim from here) captured at  https://bugs.eclipse.org/bugs/show_bug.cgi?id=578856#c1

Is there something which I am missing in this reasoning here?

Regards,
Manoj
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