From 85e34b239672a5d8c0d4ef01fae06f6921de9591 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Adolfo=20Ochagav=C3=ADa?= <aochagavia92@gmail.com>
Date: Sun, 11 May 2014 18:23:46 +0200
Subject: [PATCH] Improved example code in Option

---
 src/libcore/option.rs | 27 +++++++++++++++------------
 src/libstd/option.rs  | 27 +++++++++++++++------------
 2 files changed, 30 insertions(+), 24 deletions(-)

diff --git a/src/libcore/option.rs b/src/libcore/option.rs
index fd6d174a703..886b7315152 100644
--- a/src/libcore/option.rs
+++ b/src/libcore/option.rs
@@ -30,20 +30,23 @@
 //! of a value and take action, always accounting for the `None` case.
 //!
 //! ```
-//! # // FIXME This is not the greatest first example
-//! // cow_says contains the word "moo"
-//! let cow_says = Some("moo");
-//! // dog_says does not contain a value
-//! let dog_says: Option<&str> = None;
+//! fn divide(numerator: f64, denominator: f64) -> Option<f64> {
+//!     if denominator == 0.0 {
+//!         None
+//!     } else {
+//!         Some(numerator / denominator)
+//!     }
+//! }
+//!
+//! // The return value of the function is an option
+//! let result = divide(2.0, 3.0);
 //!
 //! // Pattern match to retrieve the value
-//! match (cow_says, dog_says) {
-//!     (Some(cow_words), Some(dog_words)) => {
-//!         println!("Cow says {} and dog says {}!", cow_words, dog_words);
-//!     }
-//!     (Some(cow_words), None) => println!("Cow says {}", cow_words),
-//!     (None, Some(dog_words)) => println!("Dog says {}", dog_words),
-//!     (None, None) => println!("Cow and dog are suspiciously silent")
+//! match result {
+//!     // The division was valid
+//!     Some(x) => println!("Result: {}", x),
+//!     // The division was invalid
+//!     None    => println!("Cannot divide by 0")
 //! }
 //! ```
 //!
diff --git a/src/libstd/option.rs b/src/libstd/option.rs
index 8fbcd529b63..ad834f2b4d4 100644
--- a/src/libstd/option.rs
+++ b/src/libstd/option.rs
@@ -30,20 +30,23 @@
 //! of a value and take action, always accounting for the `None` case.
 //!
 //! ```
-//! # // FIXME This is not the greatest first example
-//! // cow_says contains the word "moo"
-//! let cow_says = Some("moo");
-//! // dog_says does not contain a value
-//! let dog_says: Option<&str> = None;
+//! fn divide(numerator: f64, denominator: f64) -> Option<f64> {
+//!     if denominator == 0.0 {
+//!         None
+//!     } else {
+//!         Some(numerator / denominator)
+//!     }
+//! }
+//!
+//! // The return value of the function is an option
+//! let result = divide(2.0, 3.0);
 //!
 //! // Pattern match to retrieve the value
-//! match (cow_says, dog_says) {
-//!     (Some(cow_words), Some(dog_words)) => {
-//!         println!("Cow says {} and dog says {}!", cow_words, dog_words);
-//!     }
-//!     (Some(cow_words), None) => println!("Cow says {}", cow_words),
-//!     (None, Some(dog_words)) => println!("Dog says {}", dog_words),
-//!     (None, None) => println!("Cow and dog are suspiciously silent")
+//! match result {
+//!     // The division was valid
+//!     Some(x) => println!("Result: {}", x),
+//!     // The division was invalid
+//!     None    => println!("Cannot divide by 0")
 //! }
 //! ```
 //!