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External module "node_modules/assert-never/index"

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Functions

Functions

assertNever

  • assertNever(value: never, noThrow?: undefined | true | false): never
  • Helper function for exhaustive checks of discriminated unions. https://basarat.gitbooks.io/typescript/docs/types/discriminated-unions.html

    example

    type A = {type: 'a'}; type B = {type: 'b'}; type Union = A | B;

    function doSomething(arg: Union) { if (arg.type === 'a') { return something; }

     if (arg.type === 'b') {
       return somethingElse;
     }
    
     // TS will error if there are other types in the union
     // Will throw an Error when called at runtime.
     // Use `assertNever(arg, true)` instead to fail silently.
     return assertNever(arg);
    

    }

    Parameters

    • value: never
    • Optional noThrow: undefined | true | false

    Returns never