Helpful Typescript Patterns

ts-patterns.ts

/** TS inference helper
 *  Wrap an interface in Prettify to give you all of the properites you expect by hovering.
 *  Use to debug really complicated inheritance based inference
 */
export type Prettify<T> = {
  [K in keyof T]: T[K]
} & {}

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/** String literal union from Enum */

enum Status {
  FAILED: 'failed',
  PENDING: 'pending,
  SUCCESS: 'success',
}

type StatusType = `${AccessPassVariant}`
// StatusType = 'failed' | 'pending' | 'success' 

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/** String literal union from Enum keys */

enum Status {
  FAILED: 'failed',
  PENDING: 'pending,
  SUCCESS: 'success',
}

type StatusKeyType = keyof typeof Status
// StatusKeyType = 'FAILED' | 'PENDING' | 'SUCCESS'

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