Add variables5 to introduce shadowing (#264)

Add variables5 to introduce shadowing
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fmoko 2020-01-14 23:32:45 +01:00 committed by GitHub
commit 89c73647f1
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@ -0,0 +1,11 @@
// variables5.rs
// Make me compile! Execute the command `rustlings hint variables5` if you want a hint :)
// I AM NOT DONE
fn main() {
let number = "3";
println!("Number {}", number);
number = 3;
println!("Number {}", number);
}

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@ -41,6 +41,20 @@ value. We can't print out something that isn't there; try giving x a value!
This is an error that can cause bugs that's very easy to make in any This is an error that can cause bugs that's very easy to make in any
programming language -- thankfully the Rust compiler has caught this for us!""" programming language -- thankfully the Rust compiler has caught this for us!"""
[[exercises]]
name = "variables5"
path = "exercises/variables/variables5.rs"
mode = "compile"
hint = """
In variables3 we already learned how to make an immutable variable mutable
using a special keyword. Unfortunately this doesn't help us much in this exercise
because we want to assign a different typed value to an existing variable. Sometimes
you may also like to reuse existing variable names because you are just converting
values to different types like in this exercise.
Fortunately Rust has a powerful solution to this problem: 'Shadowing'!
You can read more about 'Shadowing' in the book's section 'Variables and Mutability'.
Try to solve this exercise afterwards using this technique."""
# IF # IF
[[exercises]] [[exercises]]