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digitalmars.D.learn - UFCS for classes with opCall( ... )

reply "ParticlePeter" <ParticlePeter gmx.de> writes:
Hello,

after watching Walters Talk about Component Programming ( link 
Bellow ) I was quite fond of his pipelining approach.
I tried the following and had to realize that this way using UFCS 
isn't working ( or I do something wrong ).

// I want to write On Canvas1 | draw Shape1 | draw Shape2 | ... 
in code ( not working ):
canvas1.shape1.shape2.draw()

// Which in essence would be ( working ):
shape2( shape1( canvas1 ) ).draw()

// With these Classes

class Canvas  {
public:
	drawTarget()  {
		// activate as Draw Target
	}
}

class Shape  {
public:
	Shape opCall( Canvas canvas ) {
		canvas.drawTarget() ;
		return this ;
	}

	Shape opCall( Shape otherShape ) {
		otherShape.draw()
		return this ;
	}

	void draw() {
		// Draw yourself Draw calls
	}
}

FYI: Its OpenGL stuff, Canvas would be the Frambuffer or FBOs, 
and Shape abstrcted draw calls. I have some more building blocks 
which would nicely fit into this pipelining.

1. Is there any way that I could make my wish syntax work with 
D's current features ?
2. Is there a reason that this does not work with UFCS, besides 
"not implemented yet" ?
3. If not 1. Would this be a valid feature requst ?

Thanks for any insights,

Cheers, ParticlePeter !


Walters Talk:
https://www.youtube.com/watch?v=cQkBOCo8UrE
Jun 01 2013
next sibling parent reply =?UTF-8?B?QWxpIMOHZWhyZWxp?= <acehreli yahoo.com> writes:
On 06/01/2013 05:22 AM, ParticlePeter wrote:


 3. If not 1. Would this be a valid feature requst ?


Looks like this request:

   http://d.puremagic.com/issues/show_bug.cgi?id=9857

Ali
Jun 01 2013
parent "ParticlePeter" <ParticlePeter gmx.de> writes:
On Sunday, 2 June 2013 at 06:07:25 UTC, Ali Çehreli wrote:

 On 06/01/2013 05:22 AM, ParticlePeter wrote:


 3. If not 1. Would this be a valid feature requst ?


 Looks like this request:

   http://d.puremagic.com/issues/show_bug.cgi?id=9857

 Ali


Uuups, how could I have missed that when searching dlang for UFCS 
? Sorry, dear Forum, and thanks, Ali, pointing out.
I read through the follow up discussion: 
http://forum.dlang.org/thread/mxsipaadpufujicmerjn forum.dlang.org?page=1

Unfortunatelly Walter didn't comment till now, which would be 
interestingm, regarding his Component Programming talk.
Jun 02 2013
prev sibling parent reply Timon Gehr <timon.gehr gmx.ch> writes:
On 06/01/2013 02:22 PM, ParticlePeter wrote:

 Hello,

 after watching Walters Talk about Component Programming ( link Bellow )
 I was quite fond of his pipelining approach.
 I tried the following and had to realize that this way using UFCS isn't
 working ( or I do something wrong ).

 // I want to write On Canvas1 | draw Shape1 | draw Shape2 | ... in code
 ( not working ):
 canvas1.shape1.shape2.draw()

 // Which in essence would be ( working ):
 shape2( shape1( canvas1 ) ).draw()
 ...


UFCS is working with opCall already.

The reason your code does not work is that UFCS only works with 
module-level symbols (and with the latest release also for locally 
imported symbols IIRC.)
Jun 02 2013
parent reply "ParticlePeter" <ParticlePeter gmx.de> writes:
 UFCS is working with opCall already.

 The reason your code does not work is that UFCS only works with 
 module-level symbols (and with the latest release also for 
 locally imported symbols IIRC.)


What do you mean with locally import symbols, isn't that the 
normal import statement ? Could you show me a working example ?

Thx.
Jun 03 2013
parent reply Timon Gehr <timon.gehr gmx.ch> writes:
On 06/03/2013 06:25 PM, ParticlePeter wrote:

 UFCS is working with opCall already.

 The reason your code does not work is that UFCS only works with
 module-level symbols (and with the latest release also for locally
 imported symbols IIRC.)


 What do you mean with locally import symbols, isn't that the normal
 import statement ? Could you show me a working example ?

 Thx.


http://dpaste.dzfl.pl/79c29c19

(What you want to do does not work, but the issue is not that UFCS does 
not work with opCall. It does.)
Jun 03 2013
parent reply "ParticlePeter" <ParticlePeter gmx.de> writes:
 http://dpaste.dzfl.pl/79c29c19

 (What you want to do does not work, but the issue is not that 
 UFCS does not work with opCall. It does.)


Thanks for the insights, undfortunatelly you're right. Is this 
behaviour on purpose, or considered a bug ?
Couldn't read that much out of the original discussion.
Jun 05 2013
parent Timon Gehr <timon.gehr gmx.ch> writes:
On 06/05/2013 05:11 PM, ParticlePeter wrote:

 http://dpaste.dzfl.pl/79c29c19

 (What you want to do does not work, but the issue is not that UFCS
 does not work with opCall. It does.)


 Thanks for the insights, undfortunatelly you're right. Is this behaviour
 on purpose, or considered a bug ?
 Couldn't read that much out of the original discussion.


It is on purpose.
Jun 05 2013