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Questions tagged [type-alias]

A type alias is a short, descriptive name for a type whose real name is longer or less descriptive than the alias. Such type members can help clarify code.

319 questions
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C++20 bit_cast vs reinterpret_cast

According to the last meeting of the ISO C++ Committee, bit-cast will be introduced in C++20 standard. I know that reinterpret_cast is not suitable for this job due to type aliasing rules but my question is why did they choose not to extend the…
bogdan tudose
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Returning constrained generics from functions and methods

I would like to create a function that returns an object that conforms to a protocol, but the protocol uses a typealias. Given the following toy example: protocol HasAwesomeness { typealias ReturnType func hasAwesomeness() ->…
edelaney05
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Does Rust have an equivalent of C's typedef?

C offers the keyword typedef which lets you alias another type: typedef unsigned int uint; This basically makes uint an alias for unsigned int. This also works with more complex types and structures too. Does Rust have a similar language feature?…
typos
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Is it bad form to make new types/datas for clarity?

I would like to know if it is bad form to do something like this: data Alignment = LeftAl | CenterAl | RightAl type Delimiter = Char type Width = Int setW :: Width -> Alignment -> Delimiter -> String -> String Rather than something like…
BryceTheGrand
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In Swift, how to extend a typealias?

I have a typealias: typealias BeaconId = [String: NSObject] I'd like to extend it by doing something like: extension BeaconId {} But this throws a compile error: Constrained extension must be declared on the unspecialized generic type…
abc123
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Aliasing with Webpack 4 and awesome-typescript loader not working

I'm currently having issue getting aliasing to work properly. From my understanding, to get aliasing to work properly with webpack you have to: Versions "typescript": "2.8.3", "webpack": "4.16.2", "webpack-cli": "3.1.0", …
darewreck
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Kotlin type-safe typealiases

I use typealiases in my Kotlin code a lot, but I wonder if I can enforce type-safety on them. typealias Latitude = Double typealias Longitude = Double fun someFun(lat: Latitude, lon: Longitude) {...} val lat: Latitude = 12.34 val lon: Longitude =…
ekaerovets
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Does Rust have an idiomatic equivalent to F# typedefs?

I'm re-writing existing code of mine in Rust 1.6 and I've found it very convenient in the source language to label a type by typedef. For example, in my card game I have a rank value in F# defined as: type Rank = uint8
Erik Uggeldahl
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Using sizeof on a typedef instead of a local variable

Like in this example (in C): typedef int type; int main() { char type; printf("sizeof(type) == %zu\n", sizeof(type)); // Outputs 1 } The output is always the size of the local variable type. When C++ removed the need to write struct before…
wefwefa3
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Is it standard practice to use type aliases to indicate parameter semantics?

Items in tuples don't have names, which means that you often don't have a clear way to document the meanings of each item. For instance, in this discriminated union: type NetworkEvent = | Message of string * string * string | ... I want to make it…
Rei Miyasaka
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Is it possible to create a template alias?

Consider the following code: template< template< typename ... > class ... Ts > struct unite { template< typename ... T > struct type : Ts< T ... > ... { }; }; // This does not work as ::type does not name a type, but a…
Daniel Frey
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Unexpected behavior with template type alias in VS2015

The following code compiles with VS15 Community and prints out "Hello". #include #include template using void_template_alias_t = void; template using Func = std::function
DaBrain
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How to access a Java static method from Scala given a type alias for that class it resides in

Given the type-alias type Cal = java.util.Calendar how can the static getInstance method be accessed? I tried the following in Scala REPL: scala> type Cal = java.util.Calendar defined type alias Cal scala> Cal.getInstance :8: error: not…
Tim Friske
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Define a typealias for the whole project

In which file can I define a typealias that works in the whole project, etc. typealias S = String
Tomas Gudmundsson
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Overhead of `using`

For my problem, I can use the using directive in two ways. They basically boil down to these options: template struct A { private: // Define our types using WrapperType = Wrapper; public: U *operator()(U *g) const { …
bremen_matt
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