• bayo (20/20) Apr 26 2007 Hello, i currently use DMD 1.013 for Windows and i cant compile this cod...
• =?ISO-8859-1?Q?Jari-Matti_M=E4kel=E4?= (7/37) Apr 26 2007 Yes, this is how inheritance works in D.
• bayo (3/47) Apr 26 2007 Realy hard to me to understand this limitation if we can "patch" it with...
• Derek Parnell (19/66) Apr 26 2007 Well "limitation" may be a bit harsh. Inheritance is available but it is
• Aarti_pl (8/36) Apr 27 2007 It seems that this behavior is similar to way mixins work. I reported it...
• kenny (1/18) Apr 30 2007 Perhaps the error can instead say something more useful like suggesting ...

bayo <bayo.fr gmail.com> writes:

Hello, i currently use DMD 1.013 for Windows and i cant compile this code


class C1 {
	public void add(int i, int j) {}
}

class C2 : C1 {
	public void add(int i) {}
}

void main() {
	C2 c = new C2();
	c.add(1, 2);
}

src\inheritance.d(16): function inheritance.C2.add (int) does not match 
parameter types (int,int)


I dont use D for a long time, but i dont remember having problem like this?

So anybody can help me:
*Is there a problem on my code?
*Is it a desired limitation?
*Can i use another version of DMD to remove this problem?

Thanks a lot for your help.

-bayo

=?ISO-8859-1?Q?Jari-Matti_M=E4kel=E4?= <jmjmak utu.fi.invalid> writes:

bayo kirjoitti:
 Hello, i currently use DMD 1.013 for Windows and i cant compile this code
 
 
 class C1 {
     public void add(int i, int j) {}
 }
 
 class C2 : C1 {
     public void add(int i) {}
 }
 
 void main() {
     C2 c = new C2();
     c.add(1, 2);
 }
 
 src\inheritance.d(16): function inheritance.C2.add (int) does not match
 parameter types (int,int)
 
 
 I dont use D for a long time, but i dont remember having problem like this?
 
 So anybody can help me:
 *Is there a problem on my code?

Yes

 *Is it a desired limitation?

Yes, this is how inheritance works in D.

 *Can i use another version of DMD to remove this problem?

No..

..but you can fix this by adding

  alias C1.add add;

to your C2 class.

 
 Thanks a lot for your help.
 
 -bayo

bayo <bayo.fr gmail.com> writes:

Jari-Matti Mäkelä a écrit :
 bayo kirjoitti:
 Hello, i currently use DMD 1.013 for Windows and i cant compile this code


 class C1 {
     public void add(int i, int j) {}
 }

 class C2 : C1 {
     public void add(int i) {}
 }

 void main() {
     C2 c = new C2();
     c.add(1, 2);
 }

 src\inheritance.d(16): function inheritance.C2.add (int) does not match
 parameter types (int,int)


 I dont use D for a long time, but i dont remember having problem like this?

 So anybody can help me:
 *Is there a problem on my code?

 
 Yes
 
 *Is it a desired limitation?

 
 Yes, this is how inheritance works in D.
 
 *Can i use another version of DMD to remove this problem?

 
 No..
 
 ..but you can fix this by adding
 
   alias C1.add add;
 
 to your C2 class.

Realy hard to me to understand this limitation if we can "patch" it with 

an alias, but thanks a lot for your fast help, it run well :)

 Thanks a lot for your help.

 -bayo

Derek Parnell <derek psych.ward> writes:

On Thu, 26 Apr 2007 20:21:04 +0200, bayo wrote:

 Jari-Matti Mäkelä a écrit :
 bayo kirjoitti:
 Hello, i currently use DMD 1.013 for Windows and i cant compile this code


 class C1 {
     public void add(int i, int j) {}
 }

 class C2 : C1 {
     public void add(int i) {}
 }

 void main() {
     C2 c = new C2();
     c.add(1, 2);
 }

 src\inheritance.d(16): function inheritance.C2.add (int) does not match
 parameter types (int,int)


 I dont use D for a long time, but i dont remember having problem like this?

 So anybody can help me:
 *Is there a problem on my code?

 
 Yes
 
 *Is it a desired limitation?

 
 Yes, this is how inheritance works in D.
 
 *Can i use another version of DMD to remove this problem?

 
 No..
 
 ..but you can fix this by adding
 
   alias C1.add add;
 
 to your C2 class.

 
 Realy hard to me to understand this limitation if we can "patch" it with 
 
 an alias, but thanks a lot for your fast help, it run well :)

Well "limitation" may be a bit harsh. Inheritance is available but it is
not as automatic as it is in some other languages.

The need for the alias is because D's rules for finding matching functions
is simple (some say simplistic). If it finds a matching name in the current
context it doesn't try to look any further (e.g in the parent class). The
'alias' is the syntax needed to explicitly bring the parent's function's
name into the current context.

In your case above, because C2 contains the name 'add' your 'c.add(1,2)'
stops looking further up the inheritance tree for a matching parameter
signature. But by adding 'alias C1.add add', it includes all the 'add'
functions in C1 into the namespace of C2.

This is how Walter wants D to work so if you have suggested improvements,
you have to convince him. (Good luck <G>)

-- 
Derek Parnell
Melbourne, Australia
"Justice for David Hicks!"
skype: derek.j.parnell

Aarti_pl <aarti interia.pl> writes:

Derek Parnell napisał(a):
 On Thu, 26 Apr 2007 20:21:04 +0200, bayo wrote:
 
 Jari-Matti Mäkelä a écrit :
 bayo kirjoitti:
 Hello, i currently use DMD 1.013 for Windows and i cant compile this code




<snip>


 Realy hard to me to understand this limitation if we can "patch" it with 

 an alias, but thanks a lot for your fast help, it run well :)

 
 Well "limitation" may be a bit harsh. Inheritance is available but it is
 not as automatic as it is in some other languages.
 
 The need for the alias is because D's rules for finding matching functions
 is simple (some say simplistic). If it finds a matching name in the current
 context it doesn't try to look any further (e.g in the parent class). The
 'alias' is the syntax needed to explicitly bring the parent's function's
 name into the current context.
 
 In your case above, because C2 contains the name 'add' your 'c.add(1,2)'
 stops looking further up the inheritance tree for a matching parameter
 signature. But by adding 'alias C1.add add', it includes all the 'add'
 functions in C1 into the namespace of C2.
 
 This is how Walter wants D to work so if you have suggested improvements,
 you have to convince him. (Good luck <G>)
 

It seems that this behavior is similar to way mixins work. I reported it 
as enhancement as current way has serious limitations.

http://d.puremagic.com/issues/show_bug.cgi?id=1182

Regards
Marcin Kuszczak
(aarti_pl)

kenny <funisher gmail.com> writes:

 Well "limitation" may be a bit harsh. Inheritance is available but it is
 not as automatic as it is in some other languages.
 
 The need for the alias is because D's rules for finding matching functions
 is simple (some say simplistic). If it finds a matching name in the current
 context it doesn't try to look any further (e.g in the parent class). The
 'alias' is the syntax needed to explicitly bring the parent's function's
 name into the current context.
 
 In your case above, because C2 contains the name 'add' your 'c.add(1,2)'
 stops looking further up the inheritance tree for a matching parameter
 signature. But by adding 'alias C1.add add', it includes all the 'add'
 functions in C1 into the namespace of C2.
 
 This is how Walter wants D to work so if you have suggested improvements,
 you have to convince him. (Good luck <G>)
 

Perhaps the error can instead say something more useful like suggesting to
alias instead.