Huh, properties?

04-19-2007, 02:46 AM

http://en.wikipedia.org/wiki/Property_%28programming%29

I like properties because they let you simplify code outside the class a lot, so I am adding them to vJass since they are also a vital requirement for xe .

But I must first decide the syntax... ... what I currently got:

Attempt A:

struct some

    private real cx
    
    method setx takes real x returns nothing
        set this.cx=x*x
    endmethod

    method geta takes nothing returns real
        return x-1.0
    endmethod

    property x set setx get cx
    property a get geta
   
endstruct

Attempt B:

struct some

    private real cx
    
    method property x= takes real x returns nothing
        set this.cx=x*x
    endmethod

    method property x takes nothing returns real
        return this.cx
    endmethod

    method property a takes nothing returns real
        return this.cx-1.0
    endmethod

   
endstruct

Attempt C:

struct some

    private real cx
    

    method set property x takes real x returns nothing
       set this.cx=x*x
    endmethod

    property x
       method get takes nothing returns real
           return this.cx
       endmethod

       method set takes real x returns nothing
           set this.cx=x*x
       endmethod
    endproperty 

    property a
       method get takes nothing returns real
           return this.cx - 1.0
       endmethod
    endproperty 

endstruct

If you got better suggestions please tell, if you actually like one of these also tell...

It is possible that you don't get it, well the three examples would have the same effect:

example:

function tes takes some s returns nothing
   set s.x= 2.0
   call BJDebugMsg(R2S(s.x)+" , "+R2S(s.a)) //"4.0 , 3.0"
endfunction

04-19-2007, 03:45 AM	#2
moyack	I propose attempt C, it's is easier to understand IMO, and it allows to define read only, write only and read/write properties. GOGOGO Vex!!!

04-19-2007, 03:56 AM	#3
Vexorian	well, all of the attempts allow all of those.

04-19-2007, 04:02 AM	#4
moyack	yes, but it's more readable and more logical, at least for me :)

04-19-2007, 05:40 AM

PipeDream

Option A seems shortest. One way you might make it even briefer for a class with many properties is to allow specifying multiple property links on one line, like

JASS:

readproperty x with getx, a with geta
writeproperty x with setx
accessproperty z with setz getz

access would mean read and write, but that syntax with the read and write functions specified based on order sucks
What about this:

JASS:

property getx reads x, setx writes x, geta reads a

04-19-2007, 07:38 AM	#6
MaD[Lion]	pipedream's method is the one i like most. Its easy to understand and still u cna add many properties in one line.

04-19-2007, 01:11 PM	#7
Vexorian	I don't really think many properties in a line is good at all... I think that maybe pipedream's second example got the properties and members reversed? JASS: property x reads cx, writes setx property a reads geta

04-19-2007, 01:19 PM	#8
Toink	We don't even know what scopes, methods and privates are and you're adding another one? >_> Anyways, I like Attempt B and PipeDream's version. They're easy to understand.

04-19-2007, 01:32 PM	#9
Vexorian	After properties the remaining changes to the syntax are: - enums (but we need type safety before adding them) - Wrapers (maybe type safety would be a good idea) - defines (although I am still not sure) Then it is all done with vJass

04-19-2007, 01:56 PM	#10
MaD[Lion]	hmm i re read pipedreams syntax... and found it a bit confusing with readproperties ect... I like this form: JASS: property x: set with setx get with cx property a: get with geta i like the "with" word, makes the thinking faster and easier, since its more logical for me to think like that.

04-19-2007, 03:51 PM	#11
PitzerMike	I'm all for Attempt C. It's the closest you can get to original JASS syntax. The other attempts obviously already caused confusion and mix-ups.

04-19-2007, 04:59 PM

#12

Vexorian

I noticed that the C I submitted had some garbage code

Attempt C:

struct some

    private real cx
    

    method set property x takes real x returns nothing
       set this.cx=x*x
    endmethod

    property x
       method get takes nothing returns real
           return this.cx
       endmethod

       method set takes real x returns nothing
           set this.cx=x*x
       endmethod
    endproperty 

    property a
       method get takes nothing returns real
           return this.cx - 1.0
       endmethod
    endproperty 

endstruct

04-19-2007, 10:25 PM	#13
PitzerMike	Yeah, i figured as much. Which one do you like, Vex?

08-04-2007, 09:30 AM	#14
cohadar	B is the best one IMHO, A an C use the set keyword == big big problems EDIT: Also A and C separate property declaration in 2 phases == more problems B is definitely the best + it is the easiest to implement.

08-04-2007, 01:07 PM	#15
Vexorian	I don't really see any "big big problems" with the things you mentioned, and none of these three is specially easier to implement .. I think I personally liked B more than the rest, have to mention that the three of them require 2 phases for the property declaration, which is unavoidable since properties need read and write, unless you make them read-only