Complete exercise: logging

exercise/logging/Cargo.toml

@@ -4,10 +4,5 @@ version = "0.1.0"
 edition = "2021"
 
 [dependencies]
-# I'm glad you came to add the `log` dependency! I got it all ready for you, just uncomment:
+log = "0.4" # I'm glad you came to add the `log` dependency! I got it all ready for you, just uncomment:
-#
+env_logger = "0.9" # And here's the env_logger dependency that you'll need in main.rs
-# log = "0.4"
-
-# And here's the env_logger dependency that you'll need in main.rs
-#
-# env_logger = "0.9"

exercise/logging/src/lib.rs

@@ -6,6 +6,8 @@
 //
 // Hint: You need to update Cargo.toml to add the `log` dependency, first.
 
+use log::{error, warn, info, debug, trace};
+
 #[derive(Debug)]
 pub struct Frog {
     energy: u8,
@@ -15,19 +17,23 @@ pub struct Frog {
 impl Frog {
     pub fn new() -> Self {
         // 2. Use debug!() to log "A new Frog has been created"
+        debug!(target: "Frog::new", "A new Frog has been created");
         Default::default()
     }
     pub fn hop(&mut self) {
         self.energy -= 1;
         // 3. Use info!() to log that a Frog hopped, and how much energy is left
+        info!(target: "Frog::hop", "A frog hopped! It has {} energy left", self.energy);
         if self.energy == 0 {
             // 4. Use warn!() to warn that the frog will go to sleep since he ran out of energy
+            warn!(target: "Frog::hop", "The frog will go to sleep since he ran out of energy");
             self.sleep();
         }
     }
     pub fn sleep(&mut self) {
         if self.sleeping {
             // 5. Use error!() to log a (non-fatal) error stating that the Frog is already asleep
+            error!(target: "Frog::sleep", "The frog is already asleep");
         } else {
             self.sleeping = true;
         }
@@ -37,9 +43,12 @@ impl Frog {
 impl Default for Frog {
     fn default() -> Self {
         // 6. Use trace!() to log that a default value was generated, with the debug representation
-        Frog {
+        let frog = Frog {
             energy: 5,
             sleeping: false,
-        }
+        };
+
+        trace!(target: "Frog::Default", "A default Frog value was generated: {:?}", frog);
+        frog
     }
 }

exercise/logging/src/main.rs

@@ -8,6 +8,7 @@ use frogger::Frog;
 
 fn main() {
     // 8. Initialize env_logger using the init() function at the top level of the library
+    env_logger::init();
 
     // 9. Run this program with `cargo run` and take a look at the default output.
     // - Now run it again with an explicit log level, like `RUST_LOG=info cargo run`