a recent discussion ( 
http://forum.dlang.org/thread/kvje4r$1tff$1...@digitalmars.com ) about the 
official enum dox ( http://dlang.org/enum.html ) was not conclusive whether

        enum IDENTIFIER;

is officially allowed/supported. jacob pointed out that it has an important use case in 
that it can serve as UDA. as UDAs are fairly new, this cannot be the reason why this 
syntax was allowed in the first place though, *if* it is allowed. also, it might be used 
in meta stuff similar to "#define IDENTIFIER" in C - playing with this idea i 
run into this issue...

while much code behaves with such an empty enum declaration,

        writeln( __traits(compiles, IDENTIFIER) );      // true
        writeln( is( IDENTIFIER == enum ) );                    // true

typeof() is not happy at all (DMD 2.063.2):

        writeln( typeof(IDENTIFIER).stringof );         
        // Error: argument IDENTIFIER to typeof is not an expression

typeof() expects an expression and a bare identifier is a "PrimaryExpression" ( 
http://dlang.org/expression.html#PrimaryExpression ) and hence a valid argument.

either the empty enum declaration is not allowed (and should be removed from 
the dox and throw a compilation error) or there is a bug in typeof().


/det

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