Is it necessary to define a boolean data type in TypeScript if the value is already assigned as false?

const expanded = false;

Is it possible to simplify the code above to just const expanded = false;?

I am curious if this simplification would have any advantages for the transpiler.

Answer №1

Simply put, yes, you can declare the variable like this:

public isClicked = false;

This works because TypeScript can automatically determine the type for primitive data types like boolean. In this case, the variable isClicked will be recognized as a boolean without explicitly specifying its type.

If you attempt to assign a non-boolean value to the isClicked variable elsewhere in your code, such as a string, like so:

this.isClicked = 'true';

You'll encounter an error message:

TS2322: Type '"true"' is not assignable to type 'boolean'.

Answer №2

Absolutely, the TypeScript compiler can automatically deduce the type.

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