From samhooper256 at gmail.com  Fri Jun 19 00:38:34 2020
From: samhooper256 at gmail.com (Sam Hooper)
Date: Fri, 19 Jun 2020 00:38:34 -0000
Subject: JLS Technical Amguity
Message-ID: <CANfdaS2MOuxPAF-Kr7hhadEh307JUALqSKWcsBNBisy2N8Kj=A@mail.gmail.com>

Hi,
There appears to be a technical ambiguity in the JLS 14. The restricted
identifier yield is allowed as the name of a type variable when, according
to the specification, it should not be. The following compiles fine:
class Outer<yield>{

class Inner<yield>{

<yield> void method() {}

}

}

which it should not according to the following productions from JLS 14:

TypeParameters:
< TypeParameterList
<https://docs.oracle.com/javase/specs/jls/se14/html/jls-8.html#jls-TypeParameterList>
 >
TypeParameterList:
TypeParameter
<https://docs.oracle.com/javase/specs/jls/se14/html/jls-4.html#jls-TypeParameter>
 {, TypeParameter
<https://docs.oracle.com/javase/specs/jls/se14/html/jls-4.html#jls-TypeParameter>
}
TypeParameter:
{TypeParameterModifier
<https://docs.oracle.com/javase/specs/jls/se14/html/jls-4.html#jls-TypeParameterModifier>
} TypeIdentifier
<https://docs.oracle.com/javase/specs/jls/se14/html/jls-3.html#jls-TypeIdentifier>
 [TypeBound
<https://docs.oracle.com/javase/specs/jls/se14/html/jls-4.html#jls-TypeBound>
]
TypeIdentifier:
Identifier
<https://docs.oracle.com/javase/specs/jls/se14/html/jls-3.html#jls-Identifier>
 but not var or yield

Thanks for your time.

-Sam Hooper