• Mike Parker (14/14) Jun 15 2004 I know casting from an array of classes to an array of interfaces is not...
• Ivan Senji (4/18) Jun 15 2004 Are you sure? I tried this (now and before) and it works.
• Mike Parker (13/15) Jun 15 2004 I'm sure. dmd 0.92 on Windows. Here's my exact code sans comments:
• Regan Heath (6/22) Jun 15 2004 This compiles for me too dmd 0.92 Windows.
• Derek (21/42) Jun 15 2004 Whoa!! I am really misunderstanding Interfaces. What does an array of
• Mike Parker (8/44) Jun 15 2004 class Keyboard : EventGenerator { }
• Derek Parnell (101/146) Jun 15 2004 Okay, didn't know you could do that! Neat. I played around with this ide...
• J Anderson (5/9) Jun 16 2004 Its called polymorphism and its one of the cornerstones of object
• Derek (8/18) Jun 16 2004 Hey, I know polymorphism. Its just that I didn't know one could use an
• Matthew (6/21) Jun 16 2004 Ha! Punched cards. You lived in luxury. We only had open connections for...
• Kris (9/32) Jun 16 2004 idea
• J Anderson (5/44) Jun 16 2004 Reminds me of a futuristic movie I once saw. What was it called now? Oh...
• Mike Parker (4/25) Jun 15 2004 Ahem. Not a D bug. The error was actually one line below the one I was
• Ivan Senji (3/28) Jun 16 2004 Don't do that, it happens :)

Mike Parker <aldacron71 yahoo.com> writes:

I know casting from an array of classes to an array of interfaces is not 
allowed, but IMO this should be:

*******************************************
interface MyInterface
{
...
}

MyInterface[] interfaceArray;
*******************************************

The compiler spits out: no [] overload for type MyInterface

Doing this:
MyInterface[4] interfaceArray;

Yields this message: '4' is not an lvalue

Bug or not?

"Ivan Senji" <ivan.senji public.srce.hr> writes:

"Mike Parker" <aldacron71 yahoo.com> wrote in message
news:cank2k$3nm$1 digitaldaemon.com...
 I know casting from an array of classes to an array of interfaces is not
 allowed, but IMO this should be:

 *******************************************
 interface MyInterface
 {
 ...
 }

 MyInterface[] interfaceArray;
 *******************************************

 The compiler spits out: no [] overload for type MyInterface

Are you sure? I tried this (now and before) and it works.
At least on dmd 0.92.

 Doing this:
 MyInterface[4] interfaceArray;

 Yields this message: '4' is not an lvalue

 Bug or not?

Mike Parker <aldacron71 yahoo.com> writes:

Ivan Senji wrote:
 Are you sure? I tried this (now and before) and it works.
 At least on dmd 0.92.

I'm sure. dmd 0.92 on Windows. Here's my exact code sans comments:

******************************************

interface EventGenerator
{
public:
	
	void frame();
}

private EventGenerator[] generators;

******************************************

I've tried it without the access modifiers, without the method 
declaration, moving the brackets... it keeps spitting out the same errors.

Regan Heath <regan netwin.co.nz> writes:

On Wed, 16 Jun 2004 06:31:39 +0900, Mike Parker <aldacron71 yahoo.com> 
wrote:
 Ivan Senji wrote:
 Are you sure? I tried this (now and before) and it works.
 At least on dmd 0.92.

 I'm sure. dmd 0.92 on Windows. Here's my exact code sans comments:

 ******************************************

 interface EventGenerator
 {
 public:
 	
 	void frame();
 }

 private EventGenerator[] generators;

 ******************************************

 I've tried it without the access modifiers, without the method 
 declaration, moving the brackets... it keeps spitting out the same 
 errors.

This compiles for me too dmd 0.92 Windows.

Regan

-- 
Using M2, Opera's revolutionary e-mail client: http://www.opera.com/m2/

Derek <derek psyc.ward> writes:

On Wed, 16 Jun 2004 06:31:39 +0900, Mike Parker wrote:

 Ivan Senji wrote:
 Are you sure? I tried this (now and before) and it works.
 At least on dmd 0.92.

 
 I'm sure. dmd 0.92 on Windows. Here's my exact code sans comments:
 
 ******************************************
 
 interface EventGenerator
 {
 public:
 	
 	void frame();
 }
 
 private EventGenerator[] generators;
 
 ******************************************
 
 I've tried it without the access modifiers, without the method 
 declaration, moving the brackets... it keeps spitting out the same errors.

Whoa!! I am really misunderstanding Interfaces. What does an array of
interfaces give one? I thought that an interface was a type of instruction
to the compiler and didn't, in itself, generate any machine code.

I think of them as a set of items that when placed in a class definition,
is telling the compiler that these items are mandatory for this class. That
is, that these items must be defined for the class.

One can't instantiate an interface object. 

You can't do ...

 class Foo: generators[2]
 {
  . . . 
 }

 class Bar: generators[4]
 {
  . . . 
 }

I'm obviously missing something important here.
-- 
Derek
Melbourne, Australia

Mike Parker <aldacron71 yahoo.com> writes:

Derek wrote:
 On Wed, 16 Jun 2004 06:31:39 +0900, Mike Parker wrote:
 
 
Ivan Senji wrote:

Are you sure? I tried this (now and before) and it works.
At least on dmd 0.92.

I'm sure. dmd 0.92 on Windows. Here's my exact code sans comments:

******************************************

interface EventGenerator
{
public:
	
	void frame();
}

private EventGenerator[] generators;

******************************************

I've tried it without the access modifiers, without the method 
declaration, moving the brackets... it keeps spitting out the same errors.

 
 
 Whoa!! I am really misunderstanding Interfaces. What does an array of
 interfaces give one? I thought that an interface was a type of instruction
 to the compiler and didn't, in itself, generate any machine code.
 
 I think of them as a set of items that when placed in a class definition,
 is telling the compiler that these items are mandatory for this class. That
 is, that these items must be defined for the class.
 
 One can't instantiate an interface object. 

class Keyboard : EventGenerator { }
class Mouse : EventGenerator { }

registerGenerator(mouseObject);
registerGenerator(keyboardObject);

The registerGenerator method should be able to store any EventGenerator 
implementations in an array of EventGenerators. That's what one gets 
from an array of interfaces.

Derek Parnell <derek psych.ward> writes:

On Wed, 16 Jun 2004 07:57:58 +0900, Mike Parker wrote:

 Derek wrote:
 On Wed, 16 Jun 2004 06:31:39 +0900, Mike Parker wrote:
 
Ivan Senji wrote:

Are you sure? I tried this (now and before) and it works.
At least on dmd 0.92.

I'm sure. dmd 0.92 on Windows. Here's my exact code sans comments:

******************************************

interface EventGenerator
{
public:
	
	void frame();
}

private EventGenerator[] generators;

******************************************

I've tried it without the access modifiers, without the method 
declaration, moving the brackets... it keeps spitting out the same errors.

 
 Whoa!! I am really misunderstanding Interfaces. What does an array of
 interfaces give one? I thought that an interface was a type of instruction
 to the compiler and didn't, in itself, generate any machine code.
 
 I think of them as a set of items that when placed in a class definition,
 is telling the compiler that these items are mandatory for this class. That
 is, that these items must be defined for the class.
 
 One can't instantiate an interface object. 

 
 class Keyboard : EventGenerator { }
 class Mouse : EventGenerator { }
 
 registerGenerator(mouseObject);
 registerGenerator(keyboardObject);
 
 The registerGenerator method should be able to store any EventGenerator 
 implementations in an array of EventGenerators. That's what one gets 
 from an array of interfaces.

Okay, didn't know you could do that! Neat. I played around with this idea
and got this... 

// ----------------- start code
import std.c.stdio;

interface EventGenerator
{
public:
    int frame();
    void frame(int pVal);
}

interface ObjType
{
public:
    char[] objType();
}

class Keyboard : EventGenerator, ObjType
{
    private:
        int id = -1;
    public:
        int frame() { return id;}

        char[] objType() { return "keyboard"; }
        void frame(int pVal){ if (pVal >= 0) id = pVal; }
}
class Mouse : EventGenerator, ObjType
{
    private:
        int id = -1;

    public:
        int frame() { return id;}

        char[] objType() { return "mouse"; }

        void frame(int pVal){ if (pVal >= 0) id = pVal; }
}

class DupException
{
    private char[] MsgText;
    this(char[] pMsg)
    {
        MsgText =  pMsg;
    }
    char[] Msg() { return MsgText; }
}

private EventGenerator[] generators;

void registerGenerator(EventGenerator x)
{
    if (x.frame < 0)
    {
        x.frame = generators.length + 1;
        generators ~= x;
    }
    else
    {
        char[] buffer;
        buffer.length = 256;
        _snprintf(buffer, 256, "Duplicate generator. Frame is %d",x.frame);
        throw new DupException(buffer);
    }
}


void main()
{

    Keyboard keyboardObject = new Keyboard;
    Mouse    mouseObject    = new Mouse;

    printf("%.*s pre-reg id = %d\n",
                keyboardObject.objType,
                keyboardObject.frame());
    printf("%.*s pre-reg id = %d\n",
                mouseObject.objType,
                mouseObject.frame());

    try{
        registerGenerator(mouseObject);
        registerGenerator(keyboardObject);
        //registerGenerator(mouseObject);
    }
    catch (DupException x)
        { printf("ERROR: %.*s\n", x.Msg);
          printf("Number registered: %d\n", generators.length);
          return;
        }

    for (int i = 0; i < generators.length; i++)
    {
        int id;
        char[] t;
        id = generators[i].frame();
        if (mouseObject.frame == id)
            t = mouseObject.objType;
        else if (keyboardObject.frame == id)
            t = keyboardObject.objType;

    };

    printf("%.*s post-reg id = %d\n",
                keyboardObject.objType,
                keyboardObject.frame());
    printf("%.*s post-reg id = %d\n",
                mouseObject.objType,
                mouseObject.frame());

}// -----------------end code

-- 
Derek
Melbourne, Australia
16/Jun/04 10:57:43 AM

J Anderson <REMOVEanderson badmama.com.au> writes:

Derek Parnell wrote:

On Wed, 16 Jun 2004 07:57:58 +0900, Mike Parker wrote:

Okay, didn't know you could do that! Neat. I played around with this idea
and got this... 
  

Its called polymorphism and its one of the cornerstones of object 
orientation.

-- 
-Anderson: http://badmama.com.au/~anderson/

Derek <derek psyc.ward> writes:

On Wed, 16 Jun 2004 17:31:56 +0800, J Anderson wrote:

 Derek Parnell wrote:
 
On Wed, 16 Jun 2004 07:57:58 +0900, Mike Parker wrote:

Okay, didn't know you could do that! Neat. I played around with this idea
and got this... 
  

 Its called polymorphism and its one of the cornerstones of object 
 orientation.

Hey, I know polymorphism. Its just that I didn't know one could use an
interface as a 'property' of a class. I've not worked with modern OOP

autocoder with these new-fangled punched card thingies. ;-)


-- 
Derek
Melbourne, Australia

"Matthew" <admin stlsoft.dot.dot.dot.dot.org> writes:

"Derek" <derek psyc.ward> wrote in message
news:3jr7u6r232a8$.1791r062spmxc$.dlg 40tude.net...
 On Wed, 16 Jun 2004 17:31:56 +0800, J Anderson wrote:

 Derek Parnell wrote:

On Wed, 16 Jun 2004 07:57:58 +0900, Mike Parker wrote:

Okay, didn't know you could do that! Neat. I played around with this idea
and got this...

 Its called polymorphism and its one of the cornerstones of object
 orientation.

 Hey, I know polymorphism. Its just that I didn't know one could use an
 interface as a 'property' of a class. I've not worked with modern OOP

 autocoder with these new-fangled punched card thingies. ;-)

Ha! Punched cards. You lived in luxury. We only had open connections for a 4-bit
bus, and we had to set the bits by connecting live plugs them with conductive
surfaces from our own bodies!

Suffice to say you tried to avoid any codes involving the number 15 ...

"Kris" <someidiot earthlink.dot.dot.dot.net> writes:

"Matthew" <admin stlsoft.dot.dot.dot.dot.org> wrote in message
news:caqiuk$1inp$1 digitaldaemon.com...
 "Derek" <derek psyc.ward> wrote in message
 news:3jr7u6r232a8$.1791r062spmxc$.dlg 40tude.net...
 On Wed, 16 Jun 2004 17:31:56 +0800, J Anderson wrote:

 Derek Parnell wrote:

On Wed, 16 Jun 2004 07:57:58 +0900, Mike Parker wrote:

Okay, didn't know you could do that! Neat. I played around with this




idea
and got this...

 Its called polymorphism and its one of the cornerstones of object
 orientation.

 Hey, I know polymorphism. Its just that I didn't know one could use an
 interface as a 'property' of a class. I've not worked with modern OOP

 autocoder with these new-fangled punched card thingies. ;-)

 Ha! Punched cards. You lived in luxury. We only had open connections for a

4-bit
 bus, and we had to set the bits by connecting live plugs them with

conductive
 surfaces from our own bodies!

 Suffice to say you tried to avoid any codes involving the number 15 ...

You still 'ad body parts? Ooohhh, we use t' dreeeeaammmm o' body parts. Wor
fingers and skin 'ad all been 'acked off t' use for printer 'eads n' cable
wrap. An' wor testicles ended up in t' abacus ...

4-bit bus? Huh! You were Lucky!!

J Anderson <REMOVEanderson badmama.com.au> writes:

Kris wrote:

"Matthew" <admin stlsoft.dot.dot.dot.dot.org> wrote in message
news:caqiuk$1inp$1 digitaldaemon.com...
  

"Derek" <derek psyc.ward> wrote in message
news:3jr7u6r232a8$.1791r062spmxc$.dlg 40tude.net...
    

On Wed, 16 Jun 2004 17:31:56 +0800, J Anderson wrote:

      

Hey, I know polymorphism. Its just that I didn't know one could use an
interface as a 'property' of a class. I've not worked with modern OOP

autocoder with these new-fangled punched card thingies. ;-)
      

Ha! Punched cards. You lived in luxury. We only had open connections for a
    

4-bit
  

bus, and we had to set the bits by connecting live plugs them with
    

conductive
  

surfaces from our own bodies!

Suffice to say you tried to avoid any codes involving the number 15 ...


    

You still 'ad body parts? Ooohhh, we use t' dreeeeaammmm o' body parts. Wor
fingers and skin 'ad all been 'acked off t' use for printer 'eads n' cable
wrap. An' wor testicles ended up in t' abacus ...

4-bit bus? Huh! You were Lucky!!
  

Reminds me of a futuristic movie I once saw.  What was it called now? Oh 
the matrix.

-- 
-Anderson: http://badmama.com.au/~anderson/

Mike Parker <aldacron71 yahoo.com> writes:

Mike Parker wrote:

 Ivan Senji wrote:
 
 Are you sure? I tried this (now and before) and it works.
 At least on dmd 0.92.

 
 
 I'm sure. dmd 0.92 on Windows. Here's my exact code sans comments:
 
 ******************************************
 
 interface EventGenerator
 {
 public:
     
     void frame();
 }
 
 private EventGenerator[] generators;
 
 ******************************************
 

Ahem. Not a D bug. The error was actually one line below the one I was 
looking at, and was indeed a mistake on my part (typo). I will go stick 
my head in a hole-in-the-ground now.

"Ivan Senji" <ivan.senji public.srce.hr> writes:

"Mike Parker" <aldacron71 yahoo.com> wrote in message
news:cao09l$lbt$1 digitaldaemon.com...
 Mike Parker wrote:

 Ivan Senji wrote:

 Are you sure? I tried this (now and before) and it works.
 At least on dmd 0.92.


 I'm sure. dmd 0.92 on Windows. Here's my exact code sans comments:

 ******************************************

 interface EventGenerator
 {
 public:

     void frame();
 }

 private EventGenerator[] generators;

 ******************************************

 Ahem. Not a D bug. The error was actually one line below the one I was
 looking at, and was indeed a mistake on my part (typo). I will go stick
 my head in a hole-in-the-ground now.

Don't do that, it happens :)