Exceptions

The Exceptions module provides a set of custom error types used throughout Funkcia for type-safe error handling.

Base Error Class

TaggedError

Create tagged errors using this function to enforce _tag identifiers, making error handling easier in your application.

A function that creates a tagged error constructor. Errors created with this function have a _tag property for identification.

import { TaggedError } from 'funkcia/exceptions';

class UserNotFoundError extends TaggedError('UserNotFound') {
  constructor(message?: string) {
    super(message);
  }
}

TaggedError.is

Checks if a value is a tagged error.

import { TaggedError } from 'funkcia/exceptions';

if (TaggedError.is(error)) {
  // error is a TaggedError
}

General Exceptions

Panic

Thrown when callbacks throw inside Option or Result operations. Represents a defect in your code – just like Rust’s panic!().

If a Panic is thrown, a deviation between your software’s actual behavior and it’s expected behavior exists, causing incorrect results. It is a defect to fix, not an error to handle.

UnhandledException

A wrapper for errors caught in try/catch blocks in a Result.

NoValueError

Error used when a nullable value is converted to a Result and is null | undefined.

FailedPredicateError

Error used when a predicate check fails in a Result chain.