variables5 is confusing

[manyinsects]

It teaches about shadowing, which is not really useful if used like this (nor is it appropriate at this point in the curriculum).

[alex-ter]

At the very least I'd suggest elaborating on what's expected. Of course the hint has it, but for those who don't want to go for hints 🙂 it would be helpful to clarify that what the exercise wants is to preserve the println! lines as-is too, i.e., to have that number + 2 piece intact.

[mo8it]

Related thread on Mastodon: https://indieweb.social/@mandarvaze/112612843843263157

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@mandarvaze@indieweb.social :
variables5 seems like cheating
I understand the concept of shadowing, but this example seems forced.
No, I didn't think of the solution at first and needed hint (and then felt like I was cheated)

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@Muddobbers@infosec.exchange:
Well, looking at it, it gets the idea across of shadowing, it's just a not-immediately-visibly-evident way of teaching it to what I would consider good teaching technique
The compiler also isn't quite lending much help, that actually may be considered a bug!

[dlloyd1]

Hi,

First of all thanks for all the time and effort that's gone into rustlings, I'm finding it an excellent learning tool alongside the Rust book.

This is the first exercise that I found jarring whilst working through them.
The spelling of a number in a string felt like a distraction, for me.

For this issue, could the use of an inner and outer scope with {} help illuminate that we're looking for name shadowing specifically in this exercise? Without having to resort to the hint, I mean.

[daniel-pfeiffer]

I also find this shadowing abusive. To my mind shadowing has its place when the same thing needs to be transformed to a better representation. E.g.

let number = "3";
let number: i32 = number.parse()?;

[grillazz]

hi,
for me confusing was // TODO: Fix the compiler error by changing the line below without renaming the variable. My solution was to change not just line below but lineS below

// TODO: Fix the compiler error by changing the line below without renaming the variable.
number = "3" ; // Don't change this line
println!("Number plus two is: {}", number.parse::<i32>().unwrap() + 2); // Don't change this line

[JoelLarson]

I solved this one by creating a new scope -- not realizing that it could just be let. I think it would be worth updating the note to something like:

    // TODO: Fix the compiler error by changing the line below without renaming the variable or changing the value.

It still leaves some ambiguity about solving it with shadowing vs adding the new scope.