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typescript-monads

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import { maybe } from '../maybe.factory'; /** * Converts a Promise to a Maybe monad * * Creates a Maybe from a Promise that resolves to a value. * If the promise resolves successfully, returns Some with the resolved value. * If the promise rejects or resolves to null/undefined, returns None. * * Note on resolution preservation: This transformation preserves resolution * semantics by converting: * - Promise rejections to None values (representing failure/absence) * - Promise resolutions to Some values (representing success/presence) * * The asynchronous nature is maintained by returning a Promise that resolves to a Maybe, * rather than a Maybe directly. This allows for proper handling in asynchronous chains. * * @param promise The promise to convert to a Maybe * @returns A Promise that resolves to a Maybe containing the result * * @example * // Convert a promise to a Maybe and use in a chain * api.fetchUser(userId) * .then(promiseToMaybe) * .then(userMaybe => userMaybe.match({ * some: user => console.log(user.name), * none: () => console.log('User not found') * })) */ export function promiseToMaybe(promise) { return promise .then(function (value) { return maybe(value); }) .catch(function () { return maybe(); }); } //# sourceMappingURL=promise-to-maybe.js.map