Jass question

[CrueIIntentions]

Hey there. I was working on a few things and came across this:

function GetUnitsOfPlayerMatching takes player whichPlayer, boolexpr filter returns group
    local group g = CreateGroup()
    call GroupEnumUnitsOfPlayer(g, whichPlayer, filter)
    call DestroyBoolExpr(filter)
    return g
endfunction

Can anyone tell me what "filter" is?

 

[Bankde]

filter is the name of variable that you have created in the function line.

function GetUnitsOfPlayerMatching takes player whichPlayer, boolexpr filter returns group

That's mean this function need 2 variable to run
1. player - name of variable you created = whichPlayer
2. boolexpr - name of variable you created = filter
When you want to run the function, you will need to call this function and give 2 parameter (that's variable type of "player" and "boolexpr").
After running this function, you will get variable "g" which is type of "group"


The name of variable isn't fixed so you may change it to what you want.

Jass Language will work like C,C++. Here the tutorial http://www.cplusplus.com/doc/tutorial/functions/

 

[CrueIIntentions]

Im afraid I don't follow. In this instance I would like to get all units from certain players. How would I complete the filter function if all I need is already in the script?

 

[Adiktuz]

Im afraid I don't follow. In this instance I would like to get all units from certain players. How would I complete the filter function if all I need is already in the script?

the filter is the condition in GUI that you use to filter which units will get picked...

 

[CrueIIntentions]

In GUI, you ask for the player, the condition being the one that triggered the event. If the trigger is aready firing, and I call the units of the triggering player;

    call GroupEnumUnitsOfPlayer(g, whichPlayer,// filter - Why would I need the filter? All conditions have been met)

Sorry, I cannot seem to wrap my head around this one. Would it be possible to give me an example of the kind of use for this filter?

 

[daxtreme]

> filter - Why would I need the filter? All conditions have been met)

What do you mean they all have been met? I don't see any condition in that code apart from that very filter you're speaking of.

 

[Adiktuz]

function check takes nothing returns boolean
      return GetWidgetLife(GetFilterUnit()) > 100
endfunction

function whatthe takes nothing returns nothing
   call GroupEnumUnitsOfPlayer(g, whichPlayer, Filter(function check))
endfunction

//now this will pick every unit owned by whichplayer that has hit points > 100

//if you dont need any filter/condition you can set that parameter to null
call GroupEnumUnitsOfPlayer(g, whichPlayer, null)
//this will pick every unit owned by the player

//basically the filter function will FILTER which units will be added to the unit group

 

[jk2pach]

I allow myself to add one thing:

the Filter() are faster than Enum. In Warcraft 3, conditions (and a Filter is a kind of condition), are faster than actions. Then, for any action you want to apply on your group, you should add the things you want to do directly in your filter.