If I have an object that contains a variable of a specific type. Can I somehow access that type? The following obviously doesn’t work: public type ObjectType = object { first: Text; }; // not valid syntax! let myVar: ObjectType.first = "John"; I’d ultimately like to access the Interface of a…

[image] Mathias: If I have an object that contains a variable of a specific type. Can I somehow access that type? The following obviously doesn’t work: public type ObjectType = object { first: Text; }; // not valid syntax! let myVar: ObjectType.first = "John"; You can do this: public …

In Motoko? Not an expert but I generally do something as following: public type ObjectType = { first: Text; }; let myVar: ObjectType = { first = "John" }; // or let first: Text = "John"; let myVar: ObjectType = { first }; Does that help or I missed the point?

Thank you, that definitely helps me generally. I meant though that I could use the type Text from the object without ever creating the actual object. So no variable would directly be of type ObjectType but I could directly define a variable of sort of the specific inner type, which in that case is T…

For inner types I create other types, again not the expert and not sure it answer your question (:sweat_smile:)? public type InnerType = { first: Text; }; public type ObjectType = { something: InnerType; }; let myVar: InnerType = { first = "John" }; let myVar2: ObjectType { somethi…

Thank you for the cheatsheet! :slight_smile: I’m now confused if my question made any sense. In a way, I was wondering if I can create a sub-object that has to have let’s say 2 specific properties of the “parent” object. And if I can make that a type. public type ParentObject = { first: Text; …

Maybe using optional parameters? public type ParentObject = { first: Text; second: Int; third: ?Nat; fourth: ?Bool; }; Or union? public type RecordId = { id : Text; }; public type Record = RecordId and { data : Blob; }; But I feel like I am missing the exact answer…

@Vivienne & @peterparker I managed to do what I wanted (slightly less elegant than I hoped). I’ll have to think through if my question made generally sense or if I just thought of it the wrong way. Thanks to both of you!

interesting, thank you very much.

Can I access a specific type of an object or even a service/interface?

Developers

Vivienne December 14, 2022, 3:08pm 7

I didn’t exactly understand what you’d want to have, but I feel like you’re interested in subtyping. Could you have a look at this and this and tell me if this is useful?

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Can I access a specific type of an object or even a service/interface?

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