From 28c830f92d5b8bc8d2c57ed891d09db582a6a552 Mon Sep 17 00:00:00 2001
From: David Bailey <davidbailey00@outlook.com>
Date: Sat, 16 Jan 2021 20:42:49 +0000
Subject: [PATCH] Add errors solutions
---
exercises/error_handling/errors1.rs | 10 ++++------
exercises/error_handling/errors2.rs | 4 +---
exercises/error_handling/errors3.rs | 5 ++---
exercises/error_handling/errorsn.rs | 14 +++++++-------
4 files changed, 14 insertions(+), 19 deletions(-)
diff --git a/exercises/error_handling/errors1.rs b/exercises/error_handling/errors1.rs
index 9c24d85..830ced3 100644
--- a/exercises/error_handling/errors1.rs
+++ b/exercises/error_handling/errors1.rs
@@ -6,14 +6,12 @@
// this function to have.
// Execute `rustlings hint errors1` for hints!
-// I AM NOT DONE
-
-pub fn generate_nametag_text(name: String) -> Option<String> {
+pub fn generate_nametag_text(name: String) -> Result<String, String> {
if name.len() > 0 {
- Some(format!("Hi! My name is {}", name))
+ Ok(format!("Hi! My name is {}", name))
} else {
// Empty names aren't allowed.
- None
+ Err(String::from("`name` was empty; it must be nonempty."))
}
}
@@ -28,7 +26,7 @@ mod tests {
fn generates_nametag_text_for_a_nonempty_name() {
assert_eq!(
generate_nametag_text("Beyoncé".into()),
- Some("Hi! My name is Beyoncé".into())
+ Ok("Hi! My name is Beyoncé".into())
);
}
diff --git a/exercises/error_handling/errors2.rs b/exercises/error_handling/errors2.rs
index aad3a93..478e3e4 100644
--- a/exercises/error_handling/errors2.rs
+++ b/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)
}
diff --git a/exercises/error_handling/errors3.rs b/exercises/error_handling/errors3.rs
index 460ac5c..c7aa7dd 100644
--- a/exercises/error_handling/errors3.rs
+++ b/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<(), 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(())
}
pub fn total_cost(item_quantity: &str) -> Result<i32, ParseIntError> {
diff --git a/exercises/error_handling/errorsn.rs b/exercises/error_handling/errorsn.rs
index 5fe212b..3c24f3d 100644
--- a/exercises/error_handling/errorsn.rs
+++ b/exercises/error_handling/errorsn.rs
@@ -17,19 +17,19 @@
//
// Execute `rustlings hint errorsn` for hints :)
-// I AM NOT DONE
-
use std::error;
use std::fmt;
use std::io;
// PositiveNonzeroInteger is a struct defined below the tests.
-fn read_and_validate(b: &mut dyn io::BufRead) -> Result<PositiveNonzeroInteger, ???> {
+fn read_and_validate(
+ b: &mut dyn io::BufRead,
+) -> Result<PositiveNonzeroInteger, Box<dyn error::Error>> {
let mut line = String::new();
- b.read_line(&mut line);
- let num: i64 = line.trim().parse();
- let answer = PositiveNonzeroInteger::new(num);
- answer
+ b.read_line(&mut line)?;
+ let num: i64 = line.trim().parse()?;
+ let answer = PositiveNonzeroInteger::new(num)?;
+ Ok(answer)
}
//