www.digitalmars.com         C & C++   DMDScript  

digitalmars.D.bugs - [Issue 5843] New: Unable to format (writeln) a struct with an alias-this to long/ulong.

reply d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=5843

           Summary: Unable to format (writeln) a struct with an alias-this
                    to long/ulong.
           Product: D
           Version: D2
          Platform: Other
        OS/Version: Mac OS X
            Status: NEW
          Keywords: rejects-valid
          Severity: normal
          Priority: P2
         Component: Phobos
        AssignedTo: nobody puremagic.com
        ReportedBy: kennytm gmail.com


--- Comment #0 from kennytm gmail.com 2011-04-13 09:03:00 PDT ---
Test case:

-----
import std.stdio;

struct S {
    ulong a;
    alias a this;
}

void main() {
    writeln(S.init);
}
-----

As of 2.052, this code generates compile-time error with


/usr/include/phobos/std/conv.d(99): Error: template std.conv.toImpl(T,S) if
(!implicitlyConverts!(S,T) && isSomeString!(T) && isInputRange!(Unqual!(S)) &&
isSomeChar!(ElementType!(S))) does not match any function template declaration
/usr/include/phobos/std/conv.d(99): Error: template std.conv.toImpl(T,S) if
(!implicitlyConverts!(S,T) && isSomeString!(T) && isInputRange!(Unqual!(S)) &&
isSomeChar!(ElementType!(S))) cannot deduce template function from argument
types !(int)(S)
/usr/include/phobos/std/conv.d(99): Error: template instance errors
instantiating template
/usr/include/phobos/std/format.d(1630): Error: template instance
std.conv.to!(int).to!(S) error instantiating
/usr/include/phobos/std/format.d(335):        instantiated from here:
getNthInt!(S)
/usr/include/phobos/std/stdio.d(660):        instantiated from here:
formattedWrite!(LockingTextWriter,immutable(char),S)
/usr/include/phobos/std/stdio.d(1493):        instantiated from here:
write!(S,char)
x.d(9):        instantiated from here: writeln!(S)
/usr/include/phobos/std/format.d(335): Error: template instance
std.format.getNthInt!(S) error instantiating
/usr/include/phobos/std/stdio.d(660):        instantiated from here:
formattedWrite!(LockingTextWriter,immutable(char),S)
/usr/include/phobos/std/stdio.d(1493):        instantiated from here:
write!(S,char)
x.d(9):        instantiated from here: writeln!(S)

-- 
Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
Apr 13 2011
next sibling parent d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=5843


kennytm gmail.com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|Unable to format (writeln)  |Unable to convert a struct
                   |a struct with an alias-this |with an alias-this to
                   |to long/ulong.              |long/ulong to int, using
                   |                            |std.conv.to!int.


--- Comment #1 from kennytm gmail.com 2011-06-02 10:28:36 PDT ---
The underlying problem is to!int of the struct isn't defined.

-------------------------
import std.conv;
struct SSSS {
    long a;
    alias a this;
}
void main() {
    to!int(SSSS.init);
}
-------------------------
/usr/include/phobos/std/conv.d(99): Error: template std.conv.toImpl(T,S) if
(!implicitlyConverts!(S,T) && isSomeString!(T) && isInputRange!(Unqual!(S)) &&
isSomeChar!(ElementType!(S))) does not match any function template declaration
/usr/include/phobos/std/conv.d(99): Error: template std.conv.toImpl(T,S) if
(!implicitlyConverts!(S,T) && isSomeString!(T) && isInputRange!(Unqual!(S)) &&
isSomeChar!(ElementType!(S))) cannot deduce template function from argument
types !(int)(SSSS)
/usr/include/phobos/std/conv.d(99): Error: template instance errors
instantiating template
x.d(7): Error: template instance std.conv.to!(int).to!(SSSS) error
instantiating
-------------------------

-- 
Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
Jun 02 2011
prev sibling next sibling parent d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=5843


SomeDude <lovelydear mailmetrash.com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |lovelydear mailmetrash.com


--- Comment #2 from SomeDude <lovelydear mailmetrash.com> 2012-04-23 09:06:43
PDT ---
Both examples compile and run with 2.059 Win32.
The first one displays 0.

-- 
Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
Apr 23 2012
prev sibling parent d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=5843


Kenji Hara <k.hara.pg gmail.com> changed:

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


--- Comment #3 from Kenji Hara <k.hara.pg gmail.com> 2012-04-23 10:42:36 PDT ---
In 2.059, std.format module treats alias this type properly.

It was fixed by the pull request:
https://github.com/D-Programming-Language/phobos/pull/488

-- 
Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
Apr 23 2012