@duydang2311/attempt/dist/index.js

A functional type for error handling in JS/TS

// lib/pipe.ts
function pipe(value, ...fns) {
  let current = value;
  for (let i = 0, size = fns.length;i < size; ++i) {
    current = fns[i](current);
    if (current instanceof Promise) {
      return current.then(async (resolved) => {
        for (let j = i + 1;j < size; ++j) {
          resolved = fns[j](resolved);
          if (resolved instanceof Promise) {
            resolved = await resolved;
          }
        }
        return resolved;
      });
    }
  }
  return current;
}

// lib/attempt.ts
function attemptSync(fn) {
  return (mapException) => {
    try {
      return attemptOk(fn());
    } catch (e) {
      return attemptFail(mapException ? mapException(e) : e);
    }
  };
}
function attemptAsync(fn) {
  return async (mapException) => {
    try {
      const ret = await fn();
      if (isAttempt(ret)) {
        return ret;
      }
      return attemptOk(ret);
    } catch (e) {
      return attemptFail(mapException ? mapException(e) : e);
    }
  };
}
function attemptOk(data) {
  return {
    ok: true,
    data,
    pipe: attemptPipe
  };
}
function attemptFail(error) {
  return {
    ok: false,
    error,
    pipe: attemptPipe
  };
}
function attemptMap(f) {
  return (attempt) => {
    if (!attempt.ok) {
      return attempt;
    }
    const ret = f(attempt.data);
    if (ret instanceof Promise) {
      return ret.then(attemptOk);
    }
    return attemptOk(ret);
  };
}
function attemptFlatMap(f) {
  return (attempt) => {
    if (!attempt.ok) {
      return attempt;
    }
    return f(attempt.data);
  };
}
function attemptMapError(f) {
  return (attempt) => {
    if (attempt.ok) {
      return attempt;
    }
    const ret = f(attempt.error);
    if (ret instanceof Promise) {
      return ret.then(attemptFail);
    }
    return attemptFail(ret);
  };
}
function attemptFlatMapError(f) {
  return (attempt) => {
    if (attempt.ok) {
      return attempt;
    }
    return f(attempt.error);
  };
}
function attemptUnwrap(attempt) {
  if (!attempt.ok) {
    throw attempt.error;
  }
  return attempt.data;
}
function attemptUnwrapOr(attemptOrDefault, defaultValue) {
  if (defaultValue) {
    const attempt = attemptOrDefault;
    return attempt.ok ? attempt.data : defaultValue;
  }
  return (attempt) => attempt.ok ? attempt.data : attemptOrDefault;
}
function attemptUnwrapOrElse(attemptOrF, f) {
  if (f) {
    const attempt = attemptOrF;
    return attempt.ok ? attempt.data : f(attempt.error);
  }
  return (attempt) => attempt.ok ? attempt.data : attemptOrF(attempt.error);
}
function isAttempt(obj) {
  return typeof obj === "object" && obj !== null && "ok" in obj && typeof obj.ok === "boolean" && (obj.ok === true && ("data" in obj) || obj.ok === false && ("error" in obj));
}
var attempt = {
  sync: attemptSync,
  async: attemptAsync,
  ok: attemptOk,
  fail: attemptFail,
  map: attemptMap,
  flatMap: attemptFlatMap,
  check: isAttempt,
  mapError: attemptMapError,
  flatMapError: attemptFlatMapError,
  orElse: attemptFlatMapError,
  unwrap: attemptUnwrap,
  unwrapOr: attemptUnwrapOr,
  unwrapOrElse: attemptUnwrapOrElse
};
function attemptPipe(...fns) {
  return pipe(this, ...fns);
}
export {
  isAttempt,
  attemptUnwrapOrElse,
  attemptUnwrapOr,
  attemptUnwrap,
  attemptSync,
  attemptOk,
  attemptMapError,
  attemptMap,
  attemptFlatMapError,
  attemptFlatMap,
  attemptFail,
  attemptAsync,
  attempt
};