Questions tagged [traits]
For questions about design and implementation of traits, a code reuse approach where defined sets of methods can be used to extend a class or type
10 questions
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How are existential types different from Rust's traits?
I am investigating ways to add some form of abstract data types to a toy language.
I was reading Graydon Hoare's The Rust I Wanted Had No Future, in which he talks about existential types. I have not ...
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Implementing automatic derivation without macros?
In Rust:
#[derive(Display)]
struct Foo<T>(T);
If T conforms to the Display trait, ...
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Expressing runtime constraints with trait-bounds
I've recently listened to Corecursive episode with John A De Goes and there's one thing that really got me thinking: the idea of type class laws pertaining to performance guarantees. The example ...
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Typeclasses, traits, interfaces, protocols: is there any consistent terminology?
Many languages have some form of expressing "user-defined duck typing": defining a type by its behavior, rather than anything about the structure or data of an instance of the type itself. ...
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Approaches to enforcing contracts for standard user-definable traits
Many languages have some user-definable traits, interfaces or protocols with special status in the language's semantics or standard library, for which there is some kind of "contract" ...
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Architecture for overriding "trait" implementations many times in different contexts?
I just asked this question about Rust: Is it possible to create a default trait implementation in Rust, and then override that trait implementation somewhere else? My problem is, in my custom lang, I ...
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Quantified variables without case-based analysis in traits
In almost every functional language I know of, quantified type variables are identified using case:
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How can I reconcile “all functions are variables” with a typeclass type system?
In my WIP language, all functions are really just variables with a callable type. That is, a function call foo(bar) is parsed into the following AST:
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How could a language implement generic traits?
Take C#'s IEnumerable<T> interface. It has a singular requirement:
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What are the pros and cons of traits in comparison with interfaces?
In Rust, structs and enums may implement any number of traits, which specify certain functions. When a struct/enum implements a trait, this is where the functions are defined:
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