Support "branded" custom types

[jasperlin451]

Feature Request

Our existing codebase has a variety of existing "Branded" type definitions. For example, we have

type Url = string & {
    __brands: {
        Url: "Url";
    };
}

When creating the assert definitions, this is what I see:

export const assertUrl = (input: any): Url => {
    const __is = (input: any): input is Url => {
        return true;
    };
    if (false === __is(input))
        ((input: any, _path: string, _exceptionable: boolean = true): input is Url => {
            return true;
        })(input, "$input", true);
    return input;
};
export const assertString = (input: any): string => {
    const __is = (input: any): input is string => {
        return "string" === typeof input;
    };
    if (false === __is(input))
        ((input: any, _path: string, _exceptionable: boolean = true): input is string => {
            const $guard = (typia.createAssert as any).guard;
            return "string" === typeof input || $guard(true, {
                path: _path + "",
                expected: "string",
                value: input
            });
        })(input, "$input", true);
    return input;
};

Feature requests:

1. It would be ideal to get a warning message about types Typia doesn't understand. Right now it just assumes everything is a Url. Maybe Typia assumes you know you're only supposed to use basic types with it but you have to read the generated output to understand that.
2. Is there a way to support these branded types? I can understand that it would be hard to provide a general solution but if typia could support the user passing in some mapping (e.g. Url -> string)

[samchon]

I need to study about it, but may consume lots of time.

[samchon]

By the way, such crazy type comes from a specific library? If that, I also need to study about that for testing.

[samchon]

At first, I will ignore intersection type when an object type being used with atomic type like string.

In that case, only string type would be left. @jasperlin451 Do you agree? Then I'll patch in this week.

[jasperlin451]

The actual implementation of the weird object type is internal to our repo but I think the general concept of "Typescript brands" general involves the intersection type of those base types with some object structure.

As yes, simplifying those "nonsense" intersections down to the string or number type would be a great start.

[MatAtBread]

If you stumbled across this issue, I have patched typia to support brands. See #911 (comment)