try-catch-overloaded

This package contains function for overloading Try/Catch statements.

Motivation

Adding custom errors requires manually checking which type of error
we received in a catch block, because JS does not have catch overload. e.g.

class UserNotFoundError extends Error {
    // ... Some implementation;
}

try {
    // ... Some code that can throw UserNotFoundError;
} catch(e) {
    if (e instanceof UserNotFoundError) {
        // ... Custome error handling for this type of errors.
    }
    // ... Some other code;
}

This lead to a problem that using custom error classes creates ton of if statements if you have
custom error handling for each class of errors. So goal of this package to solve this problem by
adding a function wrapper that will handle overloading for catch statements in nice and convenient way.

Try

This function is a wrapper for that adds a way to overload catch statements.
It will return a function that has method catch on it. You can chain the .catch calls
to add an error handler for a particular type of error object. Also, you can add generic
error handler that will be called if an error was not handled by specific error handlers.
The function fill return the result returned either by the function passed to the Try function call
or by an error handler, or undefined if no value was returned.

const { Try } = require('try-catch-overloaded');

const result = Try(() => {
    // ... do something here.
    return 'Result';
}).catch(UserNotFoundError, (error) => {
    // ... Handle user not found error.
    return 'Result for User Not Found Error';
}).catch(BadArgumentsError, (error) => {
    // ... Handle bad arguments error.
}).catch((error) => {
    // ... Handle every other error that does not matches previus handlers
// Note here you should add () to execute returned function.
})();

console.log(result); // either 'Result' or 'Result for User Not Found Error' or undefined;

If it can not find appropriate error handler it will just throw the error to outer world.

try {
    Try(() => {
    })();
} catch(missConfiguredExecutorError) {
    // It will throw an error if you don't specify at least one error handler. 
}

Dynamic configuration

Because Try returns a function you can always add dynamic configuration for catch methods. Though
I personally don't see a practical application of this, but maybe someone will find this useful. \

Voice of caution: Don't use this feature, you should always define all possible error handlers, otherwise
your code is unsafe because you can miss an error due to misconfiguration. Though, you can always rely on generic error handler.

const executor = Try(() => {
    // ... some code
});

executor.catch(AlwaysAppearingError, (error) => {
    // Handle error/
})

if (needToHandleUserError) {
    executor.catch(UserError, (userError) => {
        // ... handle error.
    })
}

if (needToHandleRandomError) {
    executor.catch(RandomError, (randomError) => {
        // ... handle error;
    });
}

TODO List

• Migrate this to TS and write types.
• Add handlers for Async code.
• Write better documentation.
• Write example for usage as a callback.
• Add parameters validation