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Comment by aziis98 | Hacker News Reader

I can't wait for more languages to adopt the "?" operator [1] like the Rust one. It's just syntactic sugar for "if expr null return null" but makes it far easier to write code in a more monadic style.

(mostly waiting for this in JS and Go)

[1]: https://doc.rust-lang.org/reference/expressions/operator-exp...

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Go actually needs proper nil/null/optionality first before it can get syntax features to deal with them.

I can't wait for more languages to simply not include null at all. It makes trying to spot them in static analysis and runtime checks much easier, because you no longer need either.

The example of Rust is one where no types are nullable by default, but only if you wrap them in an `Option<T>`.

Given these two function signatures:

    pub fn getUser() -> User

    pub fn getMaybeUser() -> Option<User>

This code won't compile, because `getUser()` cannot return a `None`:

    pub fn foo() -> Option<String> {
        let user = getUser()?;
        return user.name
    }

But this code will compile:

    pub fn foo2() -> Option<String> {
        let user = getMaybeUser()?;
        return Some(user.name)
    }

(rust playground link: https://play.rust-lang.org/?version=stable&mode=debug&editio...)

In the context of the parent's example, Rust doesn't include null at all, it just has a standard Option type with a None variant. While the other mentioned languages (JS and Go) do have null, they don't necessarily need to remove it to start getting the benefits, they just need to provide standardized alternatives and get the community to follow along (and if, say, a fancy new ? operator only worked on these new types and didn't work on null in general, that would be a strong carrot).

i remember using this back in my groovy days https://groovy-lang.org/operators.html#_safe_navigation_oper...

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