Merge 5f2aff6783 into 71053101c3

Technically it's correct, but playing around with this will very quickly
throw you into having to handle `Option`s and futzing around with
`try_into`. Not really something we want to throw upon the user here.

Closes #1948.

Cargo.lock

@@ -61,9 +61,9 @@ dependencies = [
 
 [[package]]
 name = "anyhow"
-version = "1.0.81"
+version = "1.0.82"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0952808a6c2afd1aa8947271f3a60f1a6763c7b912d210184c5149b5cf147247"
+checksum = "f538837af36e6f6a9be0faa67f9a314f8119e4e4b5867c6ab40ed60360142519"
 
 [[package]]
 name = "assert_cmd"
@@ -203,9 +203,9 @@ checksum = "fea41bba32d969b513997752735605054bc0dfa92b4c56bf1189f2e174be7a10"
 
 [[package]]
 name = "either"
-version = "1.10.0"
+version = "1.11.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "11157ac094ffbdde99aa67b23417ebdd801842852b500e395a45a9c0aac03e4a"
+checksum = "a47c1c47d2f5964e29c61246e81db715514cd532db6b5116a25ea3c03d6780a2"
 
 [[package]]
 name = "encode_unicode"
@@ -390,9 +390,9 @@ checksum = "90ed8c1e510134f979dbc4f070f87d4313098b704861a105fe34231c70a3901c"
 
 [[package]]
 name = "memchr"
-version = "2.7.1"
+version = "2.7.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "523dc4f511e55ab87b694dc30d0f820d60906ef06413f93d4d7a1385599cc149"
+checksum = "6c8640c5d730cb13ebd907d8d04b52f55ac9a2eec55b440c8892f40d56c76c1d"
 
 [[package]]
 name = "mio"
@@ -495,18 +495,18 @@ dependencies = [
 
 [[package]]
 name = "proc-macro2"
-version = "1.0.79"
+version = "1.0.81"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e835ff2298f5721608eb1a980ecaee1aef2c132bf95ecc026a11b7bf3c01c02e"
+checksum = "3d1597b0c024618f09a9c3b8655b7e430397a36d23fdafec26d6965e9eec3eba"
 dependencies = [
  "unicode-ident",
 ]
 
 [[package]]
 name = "quote"
-version = "1.0.35"
+version = "1.0.36"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "291ec9ab5efd934aaf503a6466c5d5251535d108ee747472c3977cc5acc868ef"
+checksum = "0fa76aaf39101c457836aec0ce2316dbdc3ab723cdda1c6bd4e6ad4208acaca7"
 dependencies = [
  "proc-macro2",
 ]
@@ -599,18 +599,18 @@ dependencies = [
 
 [[package]]
 name = "serde"
-version = "1.0.197"
+version = "1.0.198"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3fb1c873e1b9b056a4dc4c0c198b24c3ffa059243875552b2bd0933b1aee4ce2"
+checksum = "9846a40c979031340571da2545a4e5b7c4163bdae79b301d5f86d03979451fcc"
 dependencies = [
  "serde_derive",
 ]
 
 [[package]]
 name = "serde_derive"
-version = "1.0.197"
+version = "1.0.198"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7eb0b34b42edc17f6b7cac84a52a1c5f0e1bb2227e997ca9011ea3dd34e8610b"
+checksum = "e88edab869b01783ba905e7d0153f9fc1a6505a96e4ad3018011eedb838566d9"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -619,9 +619,9 @@ dependencies = [
 
 [[package]]
 name = "serde_json"
-version = "1.0.115"
+version = "1.0.116"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "12dc5c46daa8e9fdf4f5e71b6cf9a53f2487da0e86e55808e2d35539666497dd"
+checksum = "3e17db7126d17feb94eb3fad46bf1a96b034e8aacbc2e775fe81505f8b0b2813"
 dependencies = [
  "itoa",
  "ryu",
@@ -645,15 +645,15 @@ checksum = "0fda2ff0d084019ba4d7c6f371c95d8fd75ce3524c3cb8fb653a3023f6323e64"
 
 [[package]]
 name = "strsim"
-version = "0.11.0"
+version = "0.11.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5ee073c9e4cd00e28217186dbe12796d692868f432bf2e97ee73bed0c56dfa01"
+checksum = "7da8b5736845d9f2fcb837ea5d9e2628564b3b043a70948a3f0b778838c5fb4f"
 
 [[package]]
 name = "syn"
-version = "2.0.55"
+version = "2.0.60"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "002a1b3dbf967edfafc32655d0f377ab0bb7b994aa1d32c8cc7e9b8bf3ebb8f0"
+checksum = "909518bc7b1c9b779f1bbf07f2929d35af9f0f37e47c6e9ef7f9dddc1e1821f3"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -677,9 +677,9 @@ dependencies = [
 
 [[package]]
 name = "toml_edit"
-version = "0.22.9"
+version = "0.22.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8e40bb779c5187258fd7aad0eb68cb8706a0a81fa712fbea808ab43c4b8374c4"
+checksum = "fb686a972ccef8537b39eead3968b0e8616cb5040dbb9bba93007c8e07c9215f"
 dependencies = [
  "indexmap",
  "serde",
@@ -789,7 +789,7 @@ version = "0.52.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "282be5f36a8ce781fad8c8ae18fa3f9beff57ec1b52cb3de0789201425d9a33d"
 dependencies = [
- "windows-targets 0.52.4",
+ "windows-targets 0.52.5",
 ]
 
 [[package]]
@@ -809,17 +809,18 @@ dependencies = [
 
 [[package]]
 name = "windows-targets"
-version = "0.52.4"
+version = "0.52.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7dd37b7e5ab9018759f893a1952c9420d060016fc19a472b4bb20d1bdd694d1b"
+checksum = "6f0713a46559409d202e70e28227288446bf7841d3211583a4b53e3f6d96e7eb"
 dependencies = [
- "windows_aarch64_gnullvm 0.52.4",
- "windows_aarch64_msvc 0.52.4",
- "windows_i686_gnu 0.52.4",
- "windows_i686_msvc 0.52.4",
- "windows_x86_64_gnu 0.52.4",
- "windows_x86_64_gnullvm 0.52.4",
- "windows_x86_64_msvc 0.52.4",
+ "windows_aarch64_gnullvm 0.52.5",
+ "windows_aarch64_msvc 0.52.5",
+ "windows_i686_gnu 0.52.5",
+ "windows_i686_gnullvm",
+ "windows_i686_msvc 0.52.5",
+ "windows_x86_64_gnu 0.52.5",
+ "windows_x86_64_gnullvm 0.52.5",
+ "windows_x86_64_msvc 0.52.5",
 ]
 
 [[package]]
@@ -830,9 +831,9 @@ checksum = "2b38e32f0abccf9987a4e3079dfb67dcd799fb61361e53e2882c3cbaf0d905d8"
 
 [[package]]
 name = "windows_aarch64_gnullvm"
-version = "0.52.4"
+version = "0.52.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "bcf46cf4c365c6f2d1cc93ce535f2c8b244591df96ceee75d8e83deb70a9cac9"
+checksum = "7088eed71e8b8dda258ecc8bac5fb1153c5cffaf2578fc8ff5d61e23578d3263"
 
 [[package]]
 name = "windows_aarch64_msvc"
@@ -842,9 +843,9 @@ checksum = "dc35310971f3b2dbbf3f0690a219f40e2d9afcf64f9ab7cc1be722937c26b4bc"
 
 [[package]]
 name = "windows_aarch64_msvc"
-version = "0.52.4"
+version = "0.52.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "da9f259dd3bcf6990b55bffd094c4f7235817ba4ceebde8e6d11cd0c5633b675"
+checksum = "9985fd1504e250c615ca5f281c3f7a6da76213ebd5ccc9561496568a2752afb6"
 
 [[package]]
 name = "windows_i686_gnu"
@@ -854,9 +855,15 @@ checksum = "a75915e7def60c94dcef72200b9a8e58e5091744960da64ec734a6c6e9b3743e"
 
 [[package]]
 name = "windows_i686_gnu"
-version = "0.52.4"
+version = "0.52.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b474d8268f99e0995f25b9f095bc7434632601028cf86590aea5c8a5cb7801d3"
+checksum = "88ba073cf16d5372720ec942a8ccbf61626074c6d4dd2e745299726ce8b89670"
+
+[[package]]
+name = "windows_i686_gnullvm"
+version = "0.52.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "87f4261229030a858f36b459e748ae97545d6f1ec60e5e0d6a3d32e0dc232ee9"
 
 [[package]]
 name = "windows_i686_msvc"
@@ -866,9 +873,9 @@ checksum = "8f55c233f70c4b27f66c523580f78f1004e8b5a8b659e05a4eb49d4166cca406"
 
 [[package]]
 name = "windows_i686_msvc"
-version = "0.52.4"
+version = "0.52.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1515e9a29e5bed743cb4415a9ecf5dfca648ce85ee42e15873c3cd8610ff8e02"
+checksum = "db3c2bf3d13d5b658be73463284eaf12830ac9a26a90c717b7f771dfe97487bf"
 
 [[package]]
 name = "windows_x86_64_gnu"
@@ -878,9 +885,9 @@ checksum = "53d40abd2583d23e4718fddf1ebec84dbff8381c07cae67ff7768bbf19c6718e"
 
 [[package]]
 name = "windows_x86_64_gnu"
-version = "0.52.4"
+version = "0.52.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5eee091590e89cc02ad514ffe3ead9eb6b660aedca2183455434b93546371a03"
+checksum = "4e4246f76bdeff09eb48875a0fd3e2af6aada79d409d33011886d3e1581517d9"
 
 [[package]]
 name = "windows_x86_64_gnullvm"
@@ -890,9 +897,9 @@ checksum = "0b7b52767868a23d5bab768e390dc5f5c55825b6d30b86c844ff2dc7414044cc"
 
 [[package]]
 name = "windows_x86_64_gnullvm"
-version = "0.52.4"
+version = "0.52.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "77ca79f2451b49fa9e2af39f0747fe999fcda4f5e241b2898624dca97a1f2177"
+checksum = "852298e482cd67c356ddd9570386e2862b5673c85bd5f88df9ab6802b334c596"
 
 [[package]]
 name = "windows_x86_64_msvc"
@@ -902,15 +909,15 @@ checksum = "ed94fce61571a4006852b7389a063ab983c02eb1bb37b47f8272ce92d06d9538"
 
 [[package]]
 name = "windows_x86_64_msvc"
-version = "0.52.4"
+version = "0.52.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "32b752e52a2da0ddfbdbcc6fceadfeede4c939ed16d13e648833a61dfb611ed8"
+checksum = "bec47e5bfd1bff0eeaf6d8b485cc1074891a197ab4225d504cb7a1ab88b02bf0"
 
 [[package]]
 name = "winnow"
-version = "0.6.5"
+version = "0.6.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "dffa400e67ed5a4dd237983829e66475f0a4a26938c4b04c21baede6262215b8"
+checksum = "f0c976aaaa0e1f90dbb21e9587cdaf1d9679a1cde8875c0d6bd83ab96a208352"
 dependencies = [
  "memchr",
 ]

Cargo.toml

@@ -9,17 +9,17 @@ authors = [
 edition = "2021"
 
 [dependencies]
-anyhow = "1.0.81"
+anyhow = "1.0.82"
 clap = { version = "4.5.4", features = ["derive"] }
 console = "0.15.8"
 indicatif = "0.17.8"
 notify-debouncer-mini = "0.4.1"
-serde_json = "1.0.115"
-serde = { version = "1.0.197", features = ["derive"] }
+serde_json = "1.0.116"
+serde = { version = "1.0.198", features = ["derive"] }
 shlex = "1.3.0"
-toml_edit = { version = "0.22.9", default-features = false, features = ["parse", "serde"] }
+toml_edit = { version = "0.22.11", default-features = false, features = ["parse", "serde"] }
 which = "6.0.1"
-winnow = "0.6.5"
+winnow = "0.6.6"
 
 [[bin]]
 name = "rustlings"

README.md

@@ -74,13 +74,13 @@ If you get a permission denied message, you might have to exclude the directory
 
 ## Manually
 
-Basically: Clone the repository at the latest tag, run `cargo install --path .`.
+Basically: Clone the repository at the latest tag, run `cargo install --locked --path .`.
 
 ```bash
 # find out the latest version at https://github.com/rust-lang/rustlings/releases/latest (on edit 5.6.1)
 git clone -b 5.6.1 --depth 1 https://github.com/rust-lang/rustlings
 cd rustlings
-cargo install --force --path .
+cargo install --locked --force --path .
 ```
 
 If there are installation errors, ensure that your toolchain is up to date. For the latest, run:

exercises/02_functions/README.md

@@ -1,8 +1,9 @@
 # Functions
 
 Here, you'll learn how to write functions and how the Rust compiler can help you debug errors even
-in more complex code.
+in more complex code. You will also learn what is the difference with closures.
 
 ## Further information
 
 - [How Functions Work](https://doc.rust-lang.org/book/ch03-03-how-functions-work.html)
+- [Closures](https://doc.rust-lang.org/book/ch13-01-closures.html)

exercises/02_functions/functions6.rs

@@ -0,0 +1,20 @@
+// functions6.rs
+//
+// Here you can practice special functions called `closures`, that can capture
+// variables of their parent context.
+// Fix the code below to make it compile, without changing the two closure
+// definitions.
+//
+// Execute `rustlings hint functions6` or use the `hint` watch subcommand for
+// some hints.
+
+// I AM NOT DONE
+
+fn main() {
+  let closure_1 = |input_var: u32| -> u32 {input_var + outer_var};
+  println!("Closure#1 returns {}", closure_1(5));
+
+  let closure_2 = |input_var| println!("Closure#2 (input_var {})", input_var);
+  closure_2(2);
+  closure_2("5");
+}

exercises/06_move_semantics/move_semantics7.rs

@@ -0,0 +1,27 @@
+// move_semantics6.rs
+//
+// Here you will practice how mutable/immutable borrowing works in the context
+// of a closure.
+//
+// Try to fix this code to make it compile and not panic.
+// You can't change anything except removing 1 line.
+//
+// Execute `rustlings hint move_semantics7` or use the `hint` watch subcommand
+// for a hint.
+
+// I AM NOT DONE
+
+fn main() {
+  let mut counter = 0;
+
+  let mut increment = || {
+    counter += 1;
+    println!("counter: {}", counter);
+  };
+
+  increment();
+  let _reborrowed_counter = &counter;
+  increment();
+
+  assert_eq!(counter, 2);
+}

exercises/README.md

@@ -3,7 +3,7 @@
 | Exercise               | Book Chapter        |
 | ---------------------- | ------------------- |
 | variables              | §3.1                |
-| functions              | §3.3                |
+| functions              | §3.3, §13.1         |
 | if                     | §3.5                |
 | primitive_types        | §3.2, §4.3          |
 | vecs                   | §8.1                |

info.toml

@@ -142,10 +142,7 @@ mode = "compile"
 hint = """
 The error message points to the function `sale_price` and says it expects a type
 after the `->`. This is where the function's return type should be -- take a
-look at the `is_even` function for an example!
-
-Also: Did you figure out that, technically, `u32` would be the more fitting type
-for the inputs of the functions here, since the original prices shouldn't be negative? If so, kudos!"""
+look at the `is_even` function for an example!"""
 
 [[exercises]]
 name = "functions5"
@@ -164,6 +161,21 @@ They are not the same. There are two solutions:
 1. Add a `return` ahead of `num * num;`
 2. remove `;`, make it to be `num * num`"""
 
+[[exercises]]
+name = "functions6"
+path = "exercises/02_functions/functions6.rs"
+mode = "compile"
+hint = """
+Hint FIX #1: Closures can capture variables defined in the outer context.
+
+Hint FIX #2: Closures can infer both input and returned types, when they are not
+specified in the signature. But the closure cannot be reused with different
+input types.
+
+Read more about closures in the rust book dedicated section:
+https://doc.rust-lang.org/book/ch13-01-closures.html
+"""
+
 # IF
 
 [[exercises]]
@@ -406,6 +418,20 @@ Can you figure out how?
 
 Another hint: it has to do with the `&` character."""
 
+[[exercises]]
+name = "move_semantics7"
+path = "exercises/06_move_semantics/move_semantics7.rs"
+mode = "compile"
+hint = """
+When a closure capture a variable to modify it, it borrows that variable as a
+mutable reference. In this exercise, as the closure mutably borrows `counter`
+and is called later, any attempt to reborrow `counter` in between will lead to
+an error.
+
+You cannot immutably borrow a variable if a mutable closure is
+called later in the scope.
+"""
+
 # STRUCTS
 
 [[exercises]]

install.ps1

@@ -78,7 +78,7 @@ Set-Location $path
 git checkout -q tags/$version
 
 Write-Host "Installing the 'rustlings' executable..."
-cargo install --force --path .
+cargo install --locked --force --path .
 if (!(Get-Command rustlings -ErrorAction SilentlyContinue)) {
     Write-Host "WARNING: Please check that you have '~/.cargo/bin' in your PATH environment variable!"
 }

install.sh

@@ -165,7 +165,7 @@ echo "Checking out version $Version..."
 git checkout -q ${Version}
 
 echo "Installing the 'rustlings' executable..."
-cargo install --force --path .
+cargo install --locked --force --path .
 
 if ! [ -x "$(command -v rustlings)" ]
 then