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const buttonTypeKeys = propertiesOf<typeof MyEnum>();
const stringProperties = propertiesOf<string>();
const promiseProperties = propertiesOf<Promise<unknown>>();

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// This will list all the readonly properties of MyInterface
const readonlyProperties = propertiesOf<MyInterface>({ readonly: true });
  
// This will list all the optional properties of MyInterface
const optionalProperties = propertiesOf<MyInterface>({ optional: true });

// This will list all the required properties of MyInterface
const requiredProperties = propertiesOf<MyInterface>({ optional: false });

// But feel free to ask for private readonly OR public optional properties

janjakubnanista

import { propertiesOf } from 'ts-reflection';

// FREEDOM!!!
const payloadKeys = propertiesOf<SomePayload>();

janjakubnanista

import { valuesOf } from 'ts-reflection';

// OMG SO MUCH BETTER
const buttonTypes: ButtonType[] = valuesOf<ButtonType>();

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const enumKey = ButtonType[ButtonType.PRIMARY]

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console.log(buttonTypes);

// The output does not look like what we'd expect!
['primary', 'PRIMARY', 'secondary', 'SECONDARY', 'link', 'LINK']

janjakubnanista

enum ButtonType {
  PRIMARY = 'primary',
  SECONDARY = 'secondary',
  LINK = 'link'
}

const buttonTypes: ButtonType[] = Object.values(ButtonType) as ButtonType[];

janjakubnanista

// Our new error type                          ↴
type ButtonType = 'primary' | 'secondary' | 'error' | 'link';

// This compiles fine even though we now have a new ButtonType
const buttonTypes: ButtonType[] = ['primary', 'secondary', 'link'];

janjakubnanista

// ButtonType 'link' is no longer in the array
const buttonTypes: ButtonType[] = ['primary', 'secondary'];

janjakubnanista

const buttonTypes: ButtonType[] = ['primary', 'secondary', 'link'];