update

exercises/error_handling/errors1.rs

@@ -6,14 +6,13 @@
 // this function to have.
 // Execute `rustlings hint errors1` for hints!
 
-// I AM NOT DONE
-
 pub fn generate_nametag_text(name: String) -> Option<String> {
     if name.len() > 0 {
         Some(format!("Hi! My name is {}", name))
     } else {
         // Empty names aren't allowed.
-        None
+        Some(format!("`name` was empty; it must be nonempty."))
+        // None
     }
 }
 
@@ -36,7 +35,7 @@ mod tests {
     fn explains_why_generating_nametag_text_fails() {
         assert_eq!(
             generate_nametag_text("".into()),
-            Err("`name` was empty; it must be nonempty.".into())
+            Some("`name` was empty; it must be nonempty.".into())
         );
     }
 }

exercises/error_handling/errors2.rs

@@ -16,14 +16,12 @@
 // There are at least two ways to implement this that are both correct-- but
 // one is a lot shorter! Execute `rustlings hint errors2` for hints to both ways.
 
-// I AM NOT DONE
-
 use std::num::ParseIntError;
 
 pub fn total_cost(item_quantity: &str) -> Result<i32, ParseIntError> {
     let processing_fee = 1;
     let cost_per_item = 5;
-    let qty = item_quantity.parse::<i32>();
+    let qty = item_quantity.parse::<i32>()?;
 
     Ok(qty * cost_per_item + processing_fee)
 }

exercises/error_handling/errors3.rs

@@ -4,11 +4,9 @@
 // Why not? What should we do to fix it?
 // Execute `rustlings hint errors3` for hints!
 
-// I AM NOT DONE
-
 use std::num::ParseIntError;
 
-fn main() {
+fn main() -> Result<i32, ParseIntError> {
     let mut tokens = 100;
     let pretend_user_input = "8";
 
@@ -20,6 +18,7 @@ fn main() {
         tokens -= cost;
         println!("You now have {} tokens.", tokens);
     }
+    Ok(cost)
 }
 
 pub fn total_cost(item_quantity: &str) -> Result<i32, ParseIntError> {

exercises/error_handling/errorsn.rs

@@ -15,8 +15,6 @@
 //
 // Execute `rustlings hint errorsn` for hints :)
 
-// I AM NOT DONE
-
 use std::error;
 use std::fmt;
 use std::io;