I typically dislike decorators because they are spooky action at a distance, and whenever I look at code in a language that has decorators, the code almost becomes a DSL of sorts.
Not that HoF and HoC don't tend towards the same problems, React used to be famous for how often HoC got used in the ecosystem and the confusion that caused!
Decorators are syntactic sugar for higher ordered functions. They fundamentally have the same capability, just with better ergonomics.
As such, you could write a function that takes in as an argument a class, and return a new class definition that extends the argument you provided... Or any number of other dubious practices.
@GET("/users/{id}")
function loadUser(id: int): Promise<User> {}
@PUT("/users/{id}")
function updateUser(id: int, user: User): Promise<User> {}That is TS, not Java. Not sure why the gp is calling it Java.
path("/api", () -> {
before("/*", (q, a) -> log.info("Received api call"));
path("/email", () -> {
post("/add", EmailApi.addEmail);
put("/change", EmailApi.changeEmail);
delete("/remove", EmailApi.deleteEmail);
});
path("/username", () -> {
post("/add", UserApi.addUsername);
put("/change", UserApi.changeUsername);
delete("/remove", UserApi.deleteUsername);
});
});
Shorter code is not always better code
For mature projects with experienced, cohesive teams, that’s a good thing. You want a DSL that blends right in with your fully capable base language.
But yeah, just like with any powerful feature, people can get excited and carried away.
Yes, decorators are not evil by themselves, but they allow people to make poor choices easier. Having to debug decorators, fiddling with order of execution + scope binding/closures when setting multiple decorators, can (not sure!) become a nightmare; depending on the code base. Or we just go straight to the hibernate spaghetti. Imagining having to use three decorators with the same name, but different functions, makes me not to want to work with this.
Having worked with (old) Java EE and Jakarta code bases, I've seen decorators being abused in 300 ways and breaking ABI in 600 ways, so let's hope we stay sane this time.