What is the method for determining the static type of a variable in TypeScript, allowing it to be applied to another variable?
What is the method for determining the static type of a variable in TypeScript, allowing it to be applied to another variable?
To ensure type safety in TypeScript, make use of the typeof operator which can now work with type definitions.
One practical example is when dealing with inferred types, such as creating a type-safe stub function like demonstrated below:
function originalFunction() { return 123 }
// This code will compile successfully
const stub1: typeof originalFunction = () => 456
// This code will not compile due to incorrect return type
const stub2: typeof originalFunction = () => 'string'
Your inquiry appears to lack specificity, but based on the mention of using a variable elsewhere, it seems like you may be interested in exploring generics. In the code snippet below, <T> represents the generic variable that can be utilized as a type. Users calling this function have the flexibility to define what T stands for.
function doSomethingWithT<T>(arg: T): T {
let newVariable: T;
...
return arg;
}
doSomethingWithT<boolean>(true)
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