summaryrefslogtreecommitdiffstats
path: root/src/doc/book/listings/ch13-functional-features/listing-13-01
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 12:02:58 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 12:02:58 +0000
commit698f8c2f01ea549d77d7dc3338a12e04c11057b9 (patch)
tree173a775858bd501c378080a10dca74132f05bc50 /src/doc/book/listings/ch13-functional-features/listing-13-01
parentInitial commit. (diff)
downloadrustc-698f8c2f01ea549d77d7dc3338a12e04c11057b9.tar.xz
rustc-698f8c2f01ea549d77d7dc3338a12e04c11057b9.zip
Adding upstream version 1.64.0+dfsg1.upstream/1.64.0+dfsg1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/doc/book/listings/ch13-functional-features/listing-13-01')
-rw-r--r--src/doc/book/listings/ch13-functional-features/listing-13-01/Cargo.lock7
-rw-r--r--src/doc/book/listings/ch13-functional-features/listing-13-01/Cargo.toml6
-rw-r--r--src/doc/book/listings/ch13-functional-features/listing-13-01/output.txt6
-rw-r--r--src/doc/book/listings/ch13-functional-features/listing-13-01/src/main.rs52
4 files changed, 71 insertions, 0 deletions
diff --git a/src/doc/book/listings/ch13-functional-features/listing-13-01/Cargo.lock b/src/doc/book/listings/ch13-functional-features/listing-13-01/Cargo.lock
new file mode 100644
index 000000000..6f974d1ba
--- /dev/null
+++ b/src/doc/book/listings/ch13-functional-features/listing-13-01/Cargo.lock
@@ -0,0 +1,7 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
+name = "shirt-company"
+version = "0.1.0"
diff --git a/src/doc/book/listings/ch13-functional-features/listing-13-01/Cargo.toml b/src/doc/book/listings/ch13-functional-features/listing-13-01/Cargo.toml
new file mode 100644
index 000000000..1eb392dfa
--- /dev/null
+++ b/src/doc/book/listings/ch13-functional-features/listing-13-01/Cargo.toml
@@ -0,0 +1,6 @@
+[package]
+name = "shirt-company"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
diff --git a/src/doc/book/listings/ch13-functional-features/listing-13-01/output.txt b/src/doc/book/listings/ch13-functional-features/listing-13-01/output.txt
new file mode 100644
index 000000000..b64a4d8dc
--- /dev/null
+++ b/src/doc/book/listings/ch13-functional-features/listing-13-01/output.txt
@@ -0,0 +1,6 @@
+$ cargo run
+ Compiling shirt-company v0.1.0 (file:///projects/shirt-company)
+ Finished dev [unoptimized + debuginfo] target(s) in 0.27s
+ Running `target/debug/shirt-company`
+The user with preference Some(Red) gets Red
+The user with preference None gets Blue
diff --git a/src/doc/book/listings/ch13-functional-features/listing-13-01/src/main.rs b/src/doc/book/listings/ch13-functional-features/listing-13-01/src/main.rs
new file mode 100644
index 000000000..2c87d6965
--- /dev/null
+++ b/src/doc/book/listings/ch13-functional-features/listing-13-01/src/main.rs
@@ -0,0 +1,52 @@
+#[derive(Debug, PartialEq, Copy, Clone)]
+enum ShirtColor {
+ Red,
+ Blue,
+}
+
+struct Inventory {
+ shirts: Vec<ShirtColor>,
+}
+
+impl Inventory {
+ fn giveaway(&self, user_preference: Option<ShirtColor>) -> ShirtColor {
+ user_preference.unwrap_or_else(|| self.most_stocked())
+ }
+
+ fn most_stocked(&self) -> ShirtColor {
+ let mut num_red = 0;
+ let mut num_blue = 0;
+
+ for color in &self.shirts {
+ match color {
+ ShirtColor::Red => num_red += 1,
+ ShirtColor::Blue => num_blue += 1,
+ }
+ }
+ if num_red > num_blue {
+ ShirtColor::Red
+ } else {
+ ShirtColor::Blue
+ }
+ }
+}
+
+fn main() {
+ let store = Inventory {
+ shirts: vec![ShirtColor::Blue, ShirtColor::Red, ShirtColor::Blue],
+ };
+
+ let user_pref1 = Some(ShirtColor::Red);
+ let giveaway1 = store.giveaway(user_pref1);
+ println!(
+ "The user with preference {:?} gets {:?}",
+ user_pref1, giveaway1
+ );
+
+ let user_pref2 = None;
+ let giveaway2 = store.giveaway(user_pref2);
+ println!(
+ "The user with preference {:?} gets {:?}",
+ user_pref2, giveaway2
+ );
+}