How to create a custom parameter decorator?

[totoblabla3]

export const CtxUserName = createParamDecorator((ctx: Context) => {

    const username = ctx.message?.from?.username as string
        || ctx.callbackQuery?.from?.username as string

    return username
})

[evilsprut]

See https://github.com/bukhalo/nestjs-telegraf/blob/master/sample/01-complete-app/src/common/decorators/update-type.decorator.ts