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digitalmars.D.bugs - [Issue 2210] New: Error: void initializer has no value

reply d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=2210

           Summary: Error: void initializer has no value
           Product: D
           Version: 1.032
          Platform: PC
        OS/Version: Linux
            Status: NEW
          Severity: normal
          Priority: P2
         Component: DMD
        AssignedTo: bugzilla digitalmars.com
        ReportedBy: moritzwarning web.de


template isStaticArrayTypeInst( T )
{
    const T isStaticArrayTypeInst = void;
}

Compile error:
Error: void initializer has no value


-- 
Jul 09 2008
next sibling parent d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=2210





------- Comment #1 from 2korden gmail.com  2008-07-09 11:10 -------
Please, do not hurry in posting your bug report!
The piece of code itself doesn't have any issues.

I think the issue you are talking about is this:

template instance(T) {
    const T instance = void;
}

void main() {
    int i = instance!(char[]).length;        // works at runtime
     const int i = instance!(char[]).length; // doesn't work at compile time
}

I can not judge whether it is a correct behavior or not. It just worked before
but doesn't anymore.


-- 
Jul 09 2008
prev sibling next sibling parent d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=2210





------- Comment #2 from moritzwarning web.de  2008-07-09 11:26 -------
Right, I was in a hurry. Sorry for that.

Anyway, it looks like it's no dmd bug, since the length property would be
undefined at runtime. The same should apply at compile time.


-- 
Jul 09 2008
prev sibling next sibling parent d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=2210





------- Comment #3 from 2korden gmail.com  2008-07-09 11:34 -------
I'm sorry, I didn't investigate problem deep enough. Issue is completely
different.

Let's start with a bachground, first. The following template is used to work
prior to DMD1.032 release:

private template isStaticArrayTypeInst( T )
{
    const T isStaticArrayTypeInst = void;
}


/**
 * Evaluates to true if T is a static array type.
 */
template isStaticArrayType( T )
{
    static if( is( typeof(T.length) ) && !is( typeof(T) == typeof(T.init) ) )
    {
        const bool isStaticArrayType = is( T ==
typeof(T[0])[isStaticArrayTypeInst!(T).length] );
    }
    else
    {
        const bool isStaticArrayType = false;
    }
}

But now it doesn't. I reduced the test case to the following difference:

template Test( T ) {
    const bool Test = ( is( typeof(T) == typeof(T.init) ) );
}

void main() {
    static assert( Test!(int) );
}

This asserts succeeded in DMD1.031 and fails in DMD1.032. As you see, it's a
typeof(int) issue, that was discussed last days. That's it.


-- 
Jul 09 2008
prev sibling parent d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=2210


moritzwarning web.de changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|                            |INVALID




-- 
Jul 09 2008