How to change type of GamePlay Tag (tag_view) to string?

Development Programming & Scripting Verse
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1

Hi,

I would like to use GamePlay Tag as string value on my verse code, but Error happens on it.

Please look at the following code:
I prepared GamePlay tag “Tag001” and attached it to a device on the level.
Then, in this Verse code, I tried to change type of GamePlay Tag (tag_view) to string to use Print the tag on screen.
(refering to
Type Casting and Conversion | Epic Developer Community (epicgames.com))

Expected Result: “Tag001” is printed on Fortnite log.

However, it seems that Error occur in “ToString” method and Fortnite crashes.
I cannot know why.
Please help me to find a reason and solution.

Thank you,

using { /Fortnite.com/Devices }
using { /Verse.org/Simulation }
using { /UnrealEngine.com/Temporary/Diagnostics }
using { /UnrealEngine.com/Temporary/SpatialMath }
using { /Verse.org/Random }
using { /Verse.org/Verse }
using { /UnrealEngine.com/Temporary/UI }
using { /Fortnite.com/UI }
using { /Verse.org/Colors }
using { /Verse.org/Simulation/Tags }

Tag001 := class(tag){}

<Class> := class(creative_device):
	 OnBegin<override>()<suspends>:void=
....
....

    <Method> ()<suspends>:void =
            TagView :tag_view = Device.GetTags()
            TagName :string = "{TagView}"
            ProjectLog("log_level.Error" , ?Level := log_level.Error)
            Print("{TagName}")

    # tag_view type is changed to string
    ToString(TagView: tag_view):string =
        ProjectLog("log_level.Error" , ?Level := log_level.Error)
        # Error causes here
        return "{TagView}"
2

Hey, so this is how I do it (but maybe there’s a better solution ? :thinking:)

t_chest_model := class(t_chest){}
t_chest_model_suitcase := class(t_chest_model){}
t_chest_model_dumpster := class(t_chest_model){}

GetChestModelTags()<transacts> : []t_chest_model = array{
    t_chest_model_suitcase{},
    t_chest_model_dumpster{}
}

GetChestModelFromTagView(TagView: tag_view)<transacts><decides>:chest_model=
    var RetModel : ?chest_model = false
    if(TagView.Has[t_chest_model_suitcase{}]):
        set RetModel = option{chest_model.Suitcase}
    else if(TagView.Has[t_chest_model_dumpster{}]):
        set RetModel = option{chest_model.Dumpster}
    RetModel?

chest_model := enum:
    Suitcase
    Dumpster

ToString(Model: chest_model):string=
    case(Model):
        chest_model.Suitcase => "Suitcase"
        chest_model.Dumpster => "Dumpster"

So basically we’re just converting tag_view (which can contain many tags) to an enum (chest_model) then override the ToString() method of the enum.
In my example, it will return the first tag it founds in the list. So it might not suit your needs :person_shrugging:

3

Thank you for your reply.

I tried to use your code on my Verse File but some Error occur.
Let me ask some question about it:

1, Your Code shoud be used before main class, shouldn’t it?


using { /Fortnite.com/Devices }
using { /Verse.org/Simulation }
using { /UnrealEngine.com/Temporary/Diagnostics }
using{ /Verse.org/Simulation/Tags }

# See https://dev.epicgames.com/documentation/en-us/uefn/create-your-own-device-in-verse for how to create a verse device.

Tag001 := class(tag){}

        # Error: Unknown identifier `t_chest`.(3506)
        t_chest_model := class(t_chest){}
        t_chest_model_suitcase := class(t_chest_model){}
        t_chest_model_dumpster := class(t_chest_model){}

        GetChestModelTags()<transacts> : []t_chest_model = array{
                    t_chest_model_suitcase{},
                    t_chest_model_dumpster{}
                }
        
        GetChestModelFromTagView(TagView: tag_view)<transacts><decides>:chest_model=
            var RetModel : ?chest_model = false
            # Error: This function parameter expects a value of type tag, but this argument is an incompatible value of type t_chest_model_suitcase.(3509)
            # (/localhost/CodeTest:)t_chest_model_suitcase : (/localhost/CodeTest:)t_chest_model
            if(TagView.Has[t_chest_model_suitcase{}]):
                set RetModel = option{chest_model.Suitcase}
            # Error: This function parameter expects a value of type tag, but this argument is an incompatible value of type t_chest_model_dumpster.(3509)
            # (/localhost/CodeTest:)t_chest_model_dumpster : (/localhost/CodeTest:)t_chest_model
            else if(TagView.Has[t_chest_model_dumpster{}]):
                set RetModel = option{chest_model.Dumpster}
            RetModel?

        chest_model := enum:
            Suitcase
            Dumpster

        ToString(Model: chest_model):string=
            case(Model):
                chest_model.Suitcase => "Suitcase"
                chest_model.Dumpster => "Dumpster"

# A Verse-authored creative device that can be placed in a level
EnumToString := class(creative_device):

    # Runs when the device is started in a running game
    OnBegin<override>()<suspends>:void=
        # TODO: Replace this with your code
        Print("Hello, world!")
        Print("2 + 2 = {2 + 2}")

2, As the above code comments, some Error occur on the code.
Error1: What is class “t_chest” type? Where is this defined and what is this used for?
Error2: it seems that “t_chest_model_suitcase” and “t_chest_model_dumpster” type cannot be used for “Has” member of “tag_view” class. Is there any reason that these types are used here?

Thank you.

4

Hey, yeah you’re right I forgot to send you send this :

t_chest := class(tag){}

But I assumed you knew a bit of Verse, the code is specific for my use and not meant to be copy pasted but rather analyzed and understood :smiley:

But if you want to test it still, move everything outside your device, or in another empty file :+1: