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/**
Define a [lazily evaluated](https://en.wikipedia.org/wiki/Lazy_evaluation) property on an object.
@param object - Object to add property to.
@param propertyName - Name of the property to add.
@param fn - Called the first time `propertyName` is accessed.
@example
```
import defineLazyProp = require('define-lazy-prop');
const unicorn = {
// …
};
defineLazyProp(unicorn, 'rainbow', () => expensiveComputation());
app.on('user-action', () => {
doSomething(unicorn.rainbow);
});
```
*/
declare function defineLazyProp<
ObjectType extends {[key: string]: unknown},
PropertyNameType extends string,
PropertyValueType
>(
object: ObjectType,
propertyName: PropertyNameType,
fn: () => PropertyValueType
): ObjectType & {[K in PropertyNameType]: PropertyValueType};
export = defineLazyProp;
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