@normed/refinements

Refinements

Docs

Guard unknown data with refinement calls. Typescript compatible.

This is a typescript compatible full pass composable refinement module, based on the premise that a refinement function is of the form.

<T>(path: Array<string>, v: mixed): T | RefinementError

Here the unknown value v is refined to the type T. If the refinement fails a RefinementError is returned. The path argument is used to provide a better contextual understanding of where a refinement error occurred.

Refinement functions are commonly called via the provided attemptRefine or useRefine functions. attemptRefine is of the form

<T>(RefinementFunction<T>, path: Array<string>, v: any, fallback: T) => T

while useRefine is of the form

<T>(RefinementFunction<T>) => (path: Array<string>, v: any) => T

Standard refinement functions and refinement utility functions are provided.

canRefine

Useful for type inference without modifying the value

import { MyType, refineMyType } from './myrefinements';

const x: unknown = {/* ... */}

const canRefineMyType = canRefine(refineMyType);

if(canRefineMyType([], x)) {
    // x is MyType
} else {
    // x is unknown
}

Development

• yarn run build

• yarn run format

• yarn run publish