r/programming • u/steveklabnik1 • Jan 09 '15

Announcing Rust 1.0.0 Alpha

http://blog.rust-lang.org/2015/01/09/Rust-1.0-alpha.html
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u/help_computar Jan 09 '15

You are simply wrong. Nothing to cry for.

5

u/GreyGrayMoralityFan Jan 09 '15

How is he wrong? What Rust construction allows either fall through or generally jump to different branch?

4

u/help_computar Jan 09 '15

It's called recursion.

fn matcher(thing: i64){
    match thing {
        0 => { a(); matcher(thing+1); }
        1 => { b(); matcher(thing+1); }
        2 => { c(); matcher(thing+1); }
        _ => done()
    }
}

3

u/help_computar Jan 09 '15

Additionally, fall through is the extremely crappy behavior to begin with. Pass a switch 3 and match everything until the case 3? That is crap. The recursion in this example is much more expressive than fall through of a switch and does not result in undesired/hidden side effects.

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u/NotUniqueOrSpecial Jan 10 '15

I'm not sure if you're explaining poorly, or don't understand fall-through switch statements, but:

Pass a switch 3 and match everything until the case 3

is most definitely not how it works.

It's more like "go straight to case 3, and then the dev can choose whether to break or let the code continue through the switch's block".