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Comment by mklein994 | Hacker News Reader

The syntax feels a bit Ruby-ish, doesn't it? Here's an example from the article of how they could expand the syntax in the future:

  foo.bar(..).baz(..).match {
    Variant1 => { ... }
    Variant2(quux) => { ... }
  }

Compared to some Ruby:

  5.times {
    puts "Hello world!"
  }

Note I'm by no means an expert in Ruby or Rust, this is just what I thought of when I saw the syntax.

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A .match "method" just opens the dam to "why stop there?"

I prefer Kotlin's general approach of .let and similar:

    number = foo.bar().baz().let {
      match it {
        A => 1
        B => 2
      }
    }

Now anyone has the general tool for chaining without needing library authors or language designers to create the API for them.

Neat! When working with Options/Results/Iterators, you can use `.map` [1] for exactly this purpose. It would sometimes be convenient to have something like `.map` / `.let` on unwrapped values as well.

[1] https://doc.rust-lang.org/std/option/enum.Option.html#method..., https://doc.rust-lang.org/std/result/enum.Result.html#method..., https://doc.rust-lang.org/std/iter/trait.Iterator.html#metho...

Note that in Rust, `.match` would itself provide the general way:

    let number = foo.bar().baz().match { it =>
        it + 1
    };

Re: your second example, once upon a time you could write something very similar in Rust:

  do 5.times {
    // ...
  }

Where do was just sugar for calling functions that took a closure as the last argument:

  fn foo(a: A, ..., z: Z, cl: ||) { ... }

  foo(a, ..., z, || {
    ...
  })

  do foo(a, ..., z) {
    ...
  }

In fact, before the current for ... in ... syntax, this is how foreach looping used to be done:

  do some_array.each |item| {
    ...
  }

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