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digitalmars.D.bugs - [Issue 20589] New: typeof may give wrong result in case of classes

https://issues.dlang.org/show_bug.cgi?id=20589

          Issue ID: 20589
           Summary: typeof may give wrong result in case of classes
                    defining `opCall` operator
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: normal
          Priority: P1
         Component: phobos
          Assignee: nobody puremagic.com
          Reporter: drug2004 bk.ru

```
import std;

class AClass {

        T opCall(T)(T p)
        {
                return p;
        }
}

void main(){
        Array!AClass arr;
}
```
compiles with error
```
... phobos/std/conv.d(4434): Error: need this for opCall of type pure nothrow
 nogc  safe AClass(AClass p)
```
The reason is that in std.conv.emplaceRef
```
static if (is(typeof(chunk = T(args))))
    chunk = T(args);
```
`is(typeof(chunk = T(args)))` return true but the expression `chunk = T(args);`
do not compiles nevertheless.

--
Feb 20