What is the best way to create a type that can accept either a string or a

I'm working with a map function and the parameter type is an array of strings or numbers. I've defined it as:

(param: (string | number)[]) => ...

However, I want to simplify it to:

(param: StringOrNumber)[]) => ...

Having to repeat the type declaration multiple times in different functions is reducing readability. Is there a built-in way in Typescript to simplify this, or do I need to create a custom type?

Answer №1

To create a custom type for this situation, you can define something like

type CombinedType = string | number
. By including this custom type in a declaration file (e.g. named customtypes.d.ts), you can make it globally accessible throughout your project.

For more information on declaration files, it's recommended to refer to the official documentation which may not be entirely clear at first glance. https://www.typescriptlang.org/v2/docs/handbook/declaration-files/introduction.html

Answer №2

To effectively implement this, it is important to create a new type and incorporate it consistently throughout the code. Alternatively, utilizing Array<string | number> could offer better readability in my opinion.

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