finished

exercises/advanced_errors/advanced_errs2.rs

@@ -16,8 +16,6 @@
 // 4. Complete the partial implementation of `Display` for
 //    `ParseClimateError`.
 
-// I AM NOT DONE
-
 use std::error::Error;
 use std::fmt::{self, Display, Formatter};
 use std::num::{ParseFloatError, ParseIntError};
@@ -38,7 +36,7 @@ enum ParseClimateError {
 // `ParseIntError` values.
 impl From<ParseIntError> for ParseClimateError {
     fn from(e: ParseIntError) -> Self {
-        Self::ParseInt(e)
+        ParseClimateError::ParseInt(e)
     }
 }
 
@@ -46,12 +44,15 @@ impl From<ParseIntError> for ParseClimateError {
 // `ParseFloatError` values.
 impl From<ParseFloatError> for ParseClimateError {
     fn from(e: ParseFloatError) -> Self {
-        // TODO: Complete this function
+        ParseClimateError::ParseFloat(e)
     }
 }
 
 // TODO: Implement a missing trait so that `main()` below will compile. It
 // is not necessary to implement any methods inside the missing trait.
+impl Error for ParseClimateError {
+    
+}
 
 // The `Display` trait allows for other code to obtain the error formatted
 // as a user-visible string.
@@ -64,6 +65,9 @@ impl Display for ParseClimateError {
         match self {
             NoCity => write!(f, "no city name"),
             ParseFloat(e) => write!(f, "error parsing temperature: {}", e),
+            Empty => write!(f, "empty input"),
+            BadLen => write!(f, "incorrect number of fields"),
+            ParseInt(e) => write!(f, "error parsing year: {}", e),
         }
     }
 }
@@ -88,13 +92,23 @@ impl FromStr for Climate {
     // TODO: Complete this function by making it handle the missing error
     // cases.
     fn from_str(s: &str) -> Result<Self, Self::Err> {
+        if s.len() == 0 {
+            return Err(ParseClimateError::Empty);
+        }
         let v: Vec<_> = s.split(',').collect();
         let (city, year, temp) = match &v[..] {
+            [city, _, _] if city.len() == 0 => return Err(ParseClimateError::NoCity),
             [city, year, temp] => (city.to_string(), year, temp),
             _ => return Err(ParseClimateError::BadLen),
         };
-        let year: u32 = year.parse()?;
-        let temp: f32 = temp.parse()?;
+        let year: u32 = match year.parse() {
+            Ok(year) => year,
+            Err(err) => return Err(ParseClimateError::ParseInt(err)),
+        };
+        let temp: f32 = match temp.parse() {
+            Ok(temp) => temp,
+            Err(err) => return Err(ParseClimateError::ParseFloat(err)),
+        };
         Ok(Climate { city, year, temp })
     }
 }