Initial commit

solutions/03_if/if1.rs

@@ -0,0 +1,32 @@
+fn bigger(a: i32, b: i32) -> i32 {
+    if a > b {
+        a
+    } else {
+        b
+    }
+}
+
+fn main() {
+    // You can optionally experiment here.
+}
+
+// Don't mind this for now :)
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn ten_is_bigger_than_eight() {
+        assert_eq!(10, bigger(10, 8));
+    }
+
+    #[test]
+    fn fortytwo_is_bigger_than_thirtytwo() {
+        assert_eq!(42, bigger(32, 42));
+    }
+
+    #[test]
+    fn equal_numbers() {
+        assert_eq!(42, bigger(42, 42));
+    }
+}

solutions/03_if/if2.rs

@@ -0,0 +1,35 @@
+fn picky_eater(food: &str) -> &str {
+    if food == "strawberry" {
+        "Yummy!"
+    } else if food == "potato" {
+        "I guess I can eat that."
+    } else {
+        "No thanks!"
+    }
+}
+
+fn main() {
+    // You can optionally experiment here.
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn yummy_food() {
+        assert_eq!(picky_eater("strawberry"), "Yummy!");
+    }
+
+    #[test]
+    fn neutral_food() {
+        assert_eq!(picky_eater("potato"), "I guess I can eat that.");
+    }
+
+    #[test]
+    fn default_disliked_food() {
+        assert_eq!(picky_eater("broccoli"), "No thanks!");
+        assert_eq!(picky_eater("gummy bears"), "No thanks!");
+        assert_eq!(picky_eater("literally anything"), "No thanks!");
+    }
+}

solutions/03_if/if3.rs

@@ -0,0 +1,53 @@
+fn animal_habitat(animal: &str) -> &str {
+    let identifier = if animal == "crab" {
+        1
+    } else if animal == "gopher" {
+        2
+    } else if animal == "snake" {
+        3
+    } else {
+        // Any unused identifier.
+        4
+    };
+
+    // Instead of such an identifier, you would use an enum in Rust.
+    // But we didn't get into enums yet.
+    if identifier == 1 {
+        "Beach"
+    } else if identifier == 2 {
+        "Burrow"
+    } else if identifier == 3 {
+        "Desert"
+    } else {
+        "Unknown"
+    }
+}
+
+fn main() {
+    // You can optionally experiment here.
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn gopher_lives_in_burrow() {
+        assert_eq!(animal_habitat("gopher"), "Burrow")
+    }
+
+    #[test]
+    fn snake_lives_in_desert() {
+        assert_eq!(animal_habitat("snake"), "Desert")
+    }
+
+    #[test]
+    fn crab_lives_on_beach() {
+        assert_eq!(animal_habitat("crab"), "Beach")
+    }
+
+    #[test]
+    fn unknown_animal() {
+        assert_eq!(animal_habitat("dinosaur"), "Unknown")
+    }
+}