What is the method for determining the constant array type based on its contents?

Suppose an array is declared as follows:

const array = ['a', 'b', 'c'];

The type of this array would be string[]. Is there a way to automatically determine the type based on the content, so that there is no need to specify the content again in the type definition of array? For example:

const array: ['a', 'b', 'c'] = ['a', 'b', 'c'];

Answer №1

I stumbled upon the most straightforward fix: const assertion.

const list = ['x', 'y', 'z'] as const;

You can read more about this in-depth explanation here.

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