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digitalmars.D.learn - idea for variant improvement

reply bioinfornatics <bioinfornatics fedoraproject.rog> writes:
Variant is very usefull but a function who take a variant as parameter
do not works whithout a cast. but You can assign a value form any type
in statement Variant v =3D 2u.
the code below explain well the problem
---------------
import std.string;
import std.stdio;
import std.variant;

void func( Variant param ){
    writeln( "it works" );
}

void func2( T )( T param ){
    Variant a =3D cast(Variant) param;
    writeln( "it works" );
}

void main( string[] args ){
    Variant a =3D 2u; // works
    func( a );
    //func( 2u ); // does not works
    func2( 2u );
}
----------

It will be great if function func work in all case
Nov 30 2011
parent reply Timon Gehr <timon.gehr gmx.ch> writes:
On 11/30/2011 07:53 PM, bioinfornatics wrote:

 Variant is very usefull but a function who take a variant as parameter
 do not works whithout a cast. but You can assign a value form any type
 in statement Variant v = 2u.
 the code below explain well the problem
 ---------------
 import std.string;
 import std.stdio;
 import std.variant;

 void func( Variant param ){
      writeln( "it works" );
 }

 void func2( T )( T param ){
      Variant a = cast(Variant) param;
      writeln( "it works" );
 }

 void main( string[] args ){
      Variant a = 2u; // works
      func( a );
      //func( 2u ); // does not works
      func2( 2u );
 }
 ----------

 It will be great if function func work in all case


Vote here: http://d.puremagic.com/issues/show_bug.cgi?id=7019
Nov 30 2011
parent reply bioinfornatics <bioinfornatics fedoraproject.rog> writes:
Le mercredi 30 novembre 2011 =C3=A0 22:19 +0100, Timon Gehr a =C3=A9crit :

 On 11/30/2011 07:53 PM, bioinfornatics wrote:

 Variant is very usefull but a function who take a variant as parameter
 do not works whithout a cast. but You can assign a value form any type
 in statement Variant v =3D 2u.
 the code below explain well the problem
 ---------------
 import std.string;
 import std.stdio;
 import std.variant;

 void func( Variant param ){
      writeln( "it works" );
 }

 void func2( T )( T param ){
      Variant a =3D cast(Variant) param;
      writeln( "it works" );
 }

 void main( string[] args ){
      Variant a =3D 2u; // works
      func( a );
      //func( 2u ); // does not works
      func2( 2u );
 }
 ----------

 It will be great if function func work in all case


=20
 Vote here: http://d.puremagic.com/issues/show_bug.cgi?id=3D7019


yes thanks i will do. And you you do not vote for this feature?
Nov 30 2011
parent Timon Gehr <timon.gehr gmx.ch> writes:
On 11/30/2011 11:55 PM, bioinfornatics wrote:

 Le mercredi 30 novembre 2011 à 22:19 +0100, Timon Gehr a écrit :

 On 11/30/2011 07:53 PM, bioinfornatics wrote:

 Variant is very usefull but a function who take a variant as parameter
 do not works whithout a cast. but You can assign a value form any type
 in statement Variant v = 2u.
 the code below explain well the problem
 ---------------
 import std.string;
 import std.stdio;
 import std.variant;

 void func( Variant param ){
       writeln( "it works" );
 }

 void func2( T )( T param ){
       Variant a = cast(Variant) param;
       writeln( "it works" );
 }

 void main( string[] args ){
       Variant a = 2u; // works
       func( a );
       //func( 2u ); // does not works
       func2( 2u );
 }
 ----------

 It will be great if function func work in all case


 Vote here: http://d.puremagic.com/issues/show_bug.cgi?id=7019


 yes thanks i will do. And you you do not vote for this feature?


I already have =).
http://d.puremagic.com/issues/votes.cgi?action=show_bug&bug_id=7019
Nov 30 2011