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ensurePromise()

ensurePromise<T>(schema, promise): ResultAsync<T, string>

Resolves a Promise, validates the result against a Kanon schema, and returns a ResultAsync.

Eliminates the ResultAsync.fromPromise(...).andThen(...) boilerplate when you need to fetch data and validate it in one step.

Type Parameters​

T: T​

The expected output type of the schema.

Parameters​

schema: Schema<T>​

Kanon schema to validate against.

promise: Promise<unknown>​

Promise that resolves to the value to validate.

Returns: ResultAsync<T, string>​

ResultAsync<T, string> — Ok<T> if the promise resolves and validation succeeds, Err<string> otherwise.

Since​

2.2.0

Example​

import { ensurePromise } from "pithos/bridges/ensurePromise";
import { object, string, number } from "pithos/kanon";

const UserSchema = object({ name: string(), age: number() });

ensurePromise(UserSchema, fetch("/api/user").then(r => r.json()))
  .map(user => user.name.toUpperCase());