What is the syntax for declaring a boolean or object type?

Is it possible to create a variable in TypeScript that can hold either true/false or an object of booleans? I'm still learning TS and would like some input on this syntax.

variableA: { a: boolean, b: boolean } | boolean

I found a workaround for now, but I'm curious if there's a better way to approach this.

See example here for the main issue

Answer №1

Absolutely, setting it up this way is definitely achievable.

You also have the option of creating an interface like so:

interface MyInterface {
    x: boolean;
    y: boolean;
}

let myVariable: MyInterface | boolean;

Additional Information:

if((object.treeA as customType)?.propertyX) {
    console.log('perform specific action for propertyX')
}

Answer №2

Absolutely! To create a custom type, you can use the following syntax:

type myType = { x: boolean, y: boolean } | boolean

var variable: myType = false;

console.log(variable);

variable = {x:true, y:false};

console.log(variable);

Remember that myType is a type declaration, not a variable.

Try it on Playground

Answer №3

If you want to simplify your code, consider using one of these options:

interface BooleanObjects {
    [key: string]: boolean;
};

type CustomType = BooleanObjects | boolean;

For a more concise version, you can use:

type CustomType = Record<string, boolean> | boolean;

With this setup, you can assign either a true/false value or an object containing multiple key-value pairs with boolean values to a variable of type CustomType.

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