I'm trying to figure out how to create an object based on a generic type in TypeScript but struggling with the syntax. Here's a simplified example of what I want to achieve:
myfunc<T>() : T[] {
let obj = new T();
let obj2 = new T();
return [obj, obj2];
}
The new T() doesn't compile as expected. In C#, I would use a where T : new constraint to resolve this issue. Can someone help me understand how to do the equivalent in TypeScript?
It's important to keep in mind that TypeScript types, including generics, only exist during compile time. Additionally, in JavaScript, the constructor function differs from the type of the object it creates.
If you're searching for something similar to this (assuming your constructor requires no parameters):
function bar<U>(D: { new(): U }): U[] {
return [new D(), new D()];
}
class AnotherClass {}
// here you must provide the constructor function
const arr = bar(AnotherClass);
In this scenario, D represents the constructor function used at runtime and U is the inferred type resulting from the construction process.
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