From: Martin Pitt <martin@piware.de>
Date: Sun, 29 Aug 2021 05:54:59 +0000 (+0200)
Subject: Move top-level files into concepts/
X-Git-Url: https://piware.de/gitweb/?p=learn-rust.git;a=commitdiff_plain;h=b653e9fe9d8492f2d4b5419721f7e00b392055f9;ds=sidebyside

Move top-level files into concepts/

As this now contains multiple projects, it was too messy.
---

diff --git a/Cargo.toml b/Cargo.toml
deleted file mode 100644
index 2ec172e..0000000
--- a/Cargo.toml
+++ /dev/null
@@ -1,9 +0,0 @@
-[package]
-name = "learning"
-version = "0.1.0"
-edition = "2018"
-
-# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
-
-[dependencies]
-global_counter = { version = "0.2.2", default-features = false }
diff --git a/concepts/Cargo.toml b/concepts/Cargo.toml
new file mode 100644
index 0000000..2ec172e
--- /dev/null
+++ b/concepts/Cargo.toml
@@ -0,0 +1,9 @@
+[package]
+name = "learning"
+version = "0.1.0"
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+global_counter = { version = "0.2.2", default-features = false }
diff --git a/concepts/src/lib.rs b/concepts/src/lib.rs
new file mode 100644
index 0000000..b7e5eb8
--- /dev/null
+++ b/concepts/src/lib.rs
@@ -0,0 +1,110 @@
+use std::fs::File;
+use std::io::prelude::*;
+use std::collections::HashMap;
+
+pub fn read_file(path: &str) -> Result<String, std::io::Error> {
+    let mut s = String::new();
+    File::open(path)?
+        .read_to_string(&mut s)?;
+    Ok(s)
+}
+
+// needs Copy trait, good for simple types
+pub fn largest<T: PartialOrd + Copy>(list: &[T]) -> T {
+    let mut result = list[0];
+    for &i in list {
+        if i > result {
+            result = i;
+        }
+    }
+    result
+}
+
+// expensive for large strings, don't use that
+pub fn largest_clone<T: PartialOrd + Clone>(list: &[T]) -> T {
+    let mut result = list[0].clone();
+    for i in list {
+        if *i > result {
+            result = i.clone();
+        }
+    }
+    result
+}
+
+// good for everything, but more expensive for simple types
+pub fn largest_ref<T: PartialOrd>(list: &[T]) -> &T {
+    let mut result = &list[0];
+    for i in list {
+        if i > result {
+            result = i;
+        }
+    }
+    result
+}
+
+pub fn longest<'a>(x: &'a str, y: &'a str) -> &'a str {
+    if x.len() > y.len() {
+        x
+    } else {
+        y
+    }
+}
+
+/// Wrap and cache an expensive calculation
+///
+/// This calls a closure just once for every distinct argument. Any subsequent
+/// call to `.value()` with the same argument uses the cached value.
+pub struct Cacher<T, A, V>
+where
+    T: Fn(A) -> V,
+    A: Eq + Copy + std::hash::Hash,
+    V: Copy,
+{
+    calc: T,
+    values: HashMap<A, V>,
+}
+
+impl<T, A, V> Cacher<T, A, V>
+where
+    T: Fn(A) -> V,
+    A: Eq + Copy + std::hash::Hash,
+    V: Copy,
+{
+    pub fn new(calc: T) -> Cacher<T, A, V> {
+        Cacher { calc, values: HashMap::new() }
+    }
+
+    pub fn value(&mut self, arg: A) -> V {
+        match self.values.get(&arg) {
+            Some(v) => *v,
+            None => {
+                let v = (self.calc)(arg);
+                self.values.insert(arg, v);
+                v
+            }
+        }
+    }
+}
+
+pub struct Counter5 {
+    count: u32
+}
+
+impl Counter5 {
+    pub fn new() -> Counter5 {
+        Counter5 { count: 0 }
+    }
+}
+
+impl Iterator for Counter5 {
+    type Item = u32;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        if self.count < 5 {
+            self.count += 1;
+            Some(self.count)
+        } else {
+            None
+        }
+    }
+}
diff --git a/concepts/src/main.rs b/concepts/src/main.rs
new file mode 100644
index 0000000..06d122b
--- /dev/null
+++ b/concepts/src/main.rs
@@ -0,0 +1,200 @@
+mod word_utils;
+mod lib;
+
+use std::collections::HashMap;
+use std::io::{prelude::*, ErrorKind};
+use std::fs::{self, File};
+
+use lib::*;
+use word_utils::{first_word, second_word};
+
+fn test_strings() {
+    let s = String::from("Hello world");
+    println!("first word: '{}'", first_word(&s));
+    println!("second word: '{}'", second_word(&s).unwrap());
+
+    let s2 = "hello dude blah";
+    println!("second word of single: '{}'", second_word(s2).unwrap_or("(none)"));
+
+    match second_word(s2) {
+        Some(w) => println!("match: second word of '{}' exists: {}", s2, w),
+        None => println!("match: second word of '{}' does not exist", s2),
+    }
+}
+
+fn test_vectors() {
+    let v1 = vec![1, 2, 3];
+    println!("statically initialized vector: {:?}", v1);
+
+    let mut v2: Vec<String> = Vec::new();
+    v2.push("Hello".to_string());
+    v2.push(String::from("world"));
+    println!("dynamically built vector: {:?}", v2);
+    println!("first element: {}", v2[0]);
+    for el in &mut v2 {
+        *el += "xx";
+    }
+    for el in &v2 {
+        println!("{}", el);
+    }
+}
+
+fn test_hashmaps() {
+    let mut scores = HashMap::new();
+    scores.insert("john", 10);
+    scores.insert("mary", 20);
+
+    println!("scores: {:?}", scores);
+
+    // hash map with .collect()
+    let persons = vec![("homer", 42), ("marge", 30)];
+    let collect_scores: HashMap<_, _> = persons.into_iter().collect();
+    println!("collect_scores: {:?}", collect_scores);
+
+    for (p, s) in &collect_scores {
+        println!("person {}: score {}", p, s);
+    }
+
+    println!("john's score: {}", scores.get("john").unwrap());
+    println!("jake's score: {}", scores.get("jake").unwrap_or(&-1));
+
+    // double scores
+    for (_, v) in scores.iter_mut() {
+        *v *= 2;
+    }
+    println!("scores after doubling: {:?}", scores);
+
+    // double scores of immutable hashmap (rebuild it)
+    let collect_scores: HashMap<_, _> = collect_scores.into_iter()
+        .map(|(k, v)| (k, 2 * v))
+        .collect();
+    println!("collect_scores after rebuilding with doubling: {:?}", collect_scores);
+}
+
+fn test_files() {
+    if let Ok(mut f) = File::open("Cargo.toml") {
+        let mut contents = String::new();
+        match f.read_to_string(&mut contents) {
+            Ok(len) => println!("successfully opened Cargo.toml: {:?}, contents {} bytes:\n{}\n----------", f, len, contents),
+            Err(e) => panic!("could not read file: {:?}", e)
+        }
+    } else {
+        println!("could not open Cargo.toml");
+    }
+
+    // alternative form, more specific error checking
+    let mut f = File::open("Cargo.toml").unwrap_or_else(|e| {
+        if e.kind() == ErrorKind::NotFound {
+            println!("Cargo.toml not found, falling back to /dev/null");
+            // need to return a File
+            File::open("/dev/null").unwrap()
+        } else {
+            panic!("Could not open Cargo.toml: {:?}", e);
+        }
+    });
+    let mut contents = String::new();
+    let len = f.read_to_string(&mut contents).unwrap_or_else(|e| {
+        panic!("Could not read file: {:?}", e);
+    });
+    println!("successfully opened Cargo.toml with unwrap_or_else: {:?}, contents {} bytes:\n{}\n----------", f, len, contents);
+
+    // using the '?' operator
+    match read_file("Cargo.toml") {
+        Ok(s) => println!("Cargo.toml contents:\n{}\n-------------", s),
+        Err(e) => println!("Could not open Cargo.toml: {:?}", e)
+    }
+
+    // using std API
+    match fs::read_to_string("Cargo.toml") {
+        Ok(s) => println!("Cargo.toml contents:\n{}\n-------------", s),
+        Err(e) => println!("Could not open Cargo.toml: {:?}", e)
+    }
+}
+
+fn test_generics() {
+    let num_list = vec![3, 42, -7, 100, 0];
+    println!("largest number: {}", largest(&num_list));
+    println!("num_list: {:?}", num_list);
+
+    let char_list = vec!['a', 'y', 'q', 'm'];
+    println!("largest char: {}", largest(&char_list));
+
+    let str_list = vec!["hello", "world", "blue", "planet"];
+    println!("largest str: {}", largest(&str_list));
+    println!("str_list: {:?}", str_list);
+
+    let string_list = vec!["aaaa".to_string(), "xxxxx".to_string(), "ffff".to_string()];
+    println!("largest string (with cloning): {}", largest_clone(&string_list));
+    println!("largest string (with ref): {}", largest_ref(&string_list));
+    println!("string_list: {:?}", string_list);
+
+    let s1 = String::from("abcd");
+    let l;
+    {
+        let s2 = "efghi";
+        l = longest(&s1, s2);
+    }
+    println!("longest string: {}", l);
+}
+
+fn test_closures() {
+    let mut expensive_int_result = Cacher::new(|x| {
+        println!("calculating expensive int result for {}", x);
+        2 * x
+    });
+
+    println!("1st int call for value 1: {}", expensive_int_result.value(1));
+    println!("2nd int call for value 1: {}", expensive_int_result.value(1));
+    println!("1st int call for value 2: {}", expensive_int_result.value(2));
+
+    let mut expensive_str_result = Cacher::new(|x: &str| {
+        println!("calculating expensive str result for {}", x);
+        x.len()
+    });
+
+    println!("1st int call for value abc: {}", expensive_str_result.value("abc"));
+    println!("2nd int call for value abc: {}", expensive_str_result.value("abc"));
+    println!("1st int call for value defg: {}", expensive_str_result.value("defg"));
+}
+
+fn test_iterators() {
+    let v1 = vec!["Hello", "good", "world"];
+    // implied default is .into_iter() which consumes v1
+    for s in v1.iter() {
+        println!("element: {}", s);
+    }
+    // can still use it now
+    println!("v1: {:?}", &v1);
+
+    // manual iteration
+    let mut v1_iter = v1.iter();
+    while let Some(e) = v1_iter.next() {
+        println!("while loop over iter: {}", e);
+    }
+
+    for l_element in v1.iter().filter(|x| x.contains('l')) {
+        println!("v1 element containing 'l': {}", l_element);
+    }
+
+    let v2 = vec![1, 2, 3];
+    let double_v2: Vec<_> = v2.iter().map(|x| x * 2).collect();
+    println!("doubled v2: {:?}", double_v2);
+
+    for i in v2.into_iter().map(|x| x * 3) {
+        println!("for loop triplicating v2: {}", i);
+    }
+
+    for i in Counter5::new() {
+        println!("Counter 5 value: {}", i);
+    }
+}
+
+fn main() {
+    test_strings();
+    test_vectors();
+    test_hashmaps();
+    test_files();
+    test_generics();
+    test_closures();
+    test_iterators();
+}
diff --git a/concepts/src/word_utils.rs b/concepts/src/word_utils.rs
new file mode 100644
index 0000000..e3e71bf
--- /dev/null
+++ b/concepts/src/word_utils.rs
@@ -0,0 +1,43 @@
+pub fn first_word(s: &str) -> &str {
+    for (i, &item) in s.as_bytes().iter().enumerate() {
+        if item == b' ' {
+            return &s[..i];
+        }
+    }
+
+    s
+}
+
+pub fn second_word(s: &str) -> Option<&str> {
+    for (i, &item) in s.as_bytes().iter().enumerate() {
+        if item == b' ' {
+            return Some(first_word(&s[(i + 1)..]));
+        }
+    }
+
+    None
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_first_word() {
+        assert_eq!(first_word(""), "");
+        assert_eq!(first_word("one"), "one");
+        assert_eq!(first_word("one two"), "one");
+
+        assert_eq!(first_word(&String::from("one two")), "one");
+    }
+
+    #[test]
+    fn test_second_word() {
+        assert_eq!(second_word(""), None);
+        assert_eq!(second_word("one"), None);
+        assert_eq!(second_word("one two"), Some("two"));
+        assert_eq!(second_word("one two three"), Some("two"));
+
+        assert_eq!(second_word(&String::from("one two three")), Some("two"));
+    }
+}
diff --git a/concepts/tests/test_lib.rs b/concepts/tests/test_lib.rs
new file mode 100644
index 0000000..af9bbe2
--- /dev/null
+++ b/concepts/tests/test_lib.rs
@@ -0,0 +1,51 @@
+#[macro_use]
+extern crate global_counter;
+
+use learning::*;
+
+#[test]
+fn test_longest() {
+    assert_eq!(longest("abc", "de"), "abc");
+    assert_eq!(longest("abc", "def"), "def");
+    assert_eq!(longest("abc", "defg"), "defg");
+}
+
+#[test]
+fn test_cacher_int_int() {
+    global_default_counter!(CALLED, u32);
+    let mut cacher = Cacher::new(|x| {
+        CALLED.inc();
+        2 * x
+    });
+    assert_eq!(cacher.value(1), 2);
+    assert_eq!(CALLED.get_cloned(), 1);
+    // second time cached
+    assert_eq!(cacher.value(1), 2);
+    assert_eq!(CALLED.get_cloned(), 1);
+    // re-evaluated for new value
+    assert_eq!(cacher.value(-2), -4);
+    assert_eq!(CALLED.get_cloned(), 2);
+    // old arg still cached
+    assert_eq!(cacher.value(1), 2);
+    assert_eq!(CALLED.get_cloned(), 2);
+}
+
+#[test]
+fn test_cacher_str_usize() {
+    global_default_counter!(CALLED, u32);
+    let mut cacher = Cacher::new(|x: &str| {
+        CALLED.inc();
+        x.len()
+    });
+    assert_eq!(cacher.value("abc"), 3);
+    assert_eq!(CALLED.get_cloned(), 1);
+    // second time cached
+    assert_eq!(cacher.value("abc"), 3);
+    assert_eq!(CALLED.get_cloned(), 1);
+    // re-evaluated for new value
+    assert_eq!(cacher.value("defg"), 4);
+    assert_eq!(CALLED.get_cloned(), 2);
+    // old arg still cached
+    assert_eq!(cacher.value("abc"), 3);
+    assert_eq!(CALLED.get_cloned(), 2);
+}
diff --git a/src/lib.rs b/src/lib.rs
deleted file mode 100644
index b7e5eb8..0000000
--- a/src/lib.rs
+++ /dev/null
@@ -1,110 +0,0 @@
-use std::fs::File;
-use std::io::prelude::*;
-use std::collections::HashMap;
-
-pub fn read_file(path: &str) -> Result<String, std::io::Error> {
-    let mut s = String::new();
-    File::open(path)?
-        .read_to_string(&mut s)?;
-    Ok(s)
-}
-
-// needs Copy trait, good for simple types
-pub fn largest<T: PartialOrd + Copy>(list: &[T]) -> T {
-    let mut result = list[0];
-    for &i in list {
-        if i > result {
-            result = i;
-        }
-    }
-    result
-}
-
-// expensive for large strings, don't use that
-pub fn largest_clone<T: PartialOrd + Clone>(list: &[T]) -> T {
-    let mut result = list[0].clone();
-    for i in list {
-        if *i > result {
-            result = i.clone();
-        }
-    }
-    result
-}
-
-// good for everything, but more expensive for simple types
-pub fn largest_ref<T: PartialOrd>(list: &[T]) -> &T {
-    let mut result = &list[0];
-    for i in list {
-        if i > result {
-            result = i;
-        }
-    }
-    result
-}
-
-pub fn longest<'a>(x: &'a str, y: &'a str) -> &'a str {
-    if x.len() > y.len() {
-        x
-    } else {
-        y
-    }
-}
-
-/// Wrap and cache an expensive calculation
-///
-/// This calls a closure just once for every distinct argument. Any subsequent
-/// call to `.value()` with the same argument uses the cached value.
-pub struct Cacher<T, A, V>
-where
-    T: Fn(A) -> V,
-    A: Eq + Copy + std::hash::Hash,
-    V: Copy,
-{
-    calc: T,
-    values: HashMap<A, V>,
-}
-
-impl<T, A, V> Cacher<T, A, V>
-where
-    T: Fn(A) -> V,
-    A: Eq + Copy + std::hash::Hash,
-    V: Copy,
-{
-    pub fn new(calc: T) -> Cacher<T, A, V> {
-        Cacher { calc, values: HashMap::new() }
-    }
-
-    pub fn value(&mut self, arg: A) -> V {
-        match self.values.get(&arg) {
-            Some(v) => *v,
-            None => {
-                let v = (self.calc)(arg);
-                self.values.insert(arg, v);
-                v
-            }
-        }
-    }
-}
-
-pub struct Counter5 {
-    count: u32
-}
-
-impl Counter5 {
-    pub fn new() -> Counter5 {
-        Counter5 { count: 0 }
-    }
-}
-
-impl Iterator for Counter5 {
-    type Item = u32;
-
-    fn next(&mut self) -> Option<Self::Item> {
-        if self.count < 5 {
-            self.count += 1;
-            Some(self.count)
-        } else {
-            None
-        }
-    }
-}
diff --git a/src/main.rs b/src/main.rs
deleted file mode 100644
index 06d122b..0000000
--- a/src/main.rs
+++ /dev/null
@@ -1,200 +0,0 @@
-mod word_utils;
-mod lib;
-
-use std::collections::HashMap;
-use std::io::{prelude::*, ErrorKind};
-use std::fs::{self, File};
-
-use lib::*;
-use word_utils::{first_word, second_word};
-
-fn test_strings() {
-    let s = String::from("Hello world");
-    println!("first word: '{}'", first_word(&s));
-    println!("second word: '{}'", second_word(&s).unwrap());
-
-    let s2 = "hello dude blah";
-    println!("second word of single: '{}'", second_word(s2).unwrap_or("(none)"));
-
-    match second_word(s2) {
-        Some(w) => println!("match: second word of '{}' exists: {}", s2, w),
-        None => println!("match: second word of '{}' does not exist", s2),
-    }
-}
-
-fn test_vectors() {
-    let v1 = vec![1, 2, 3];
-    println!("statically initialized vector: {:?}", v1);
-
-    let mut v2: Vec<String> = Vec::new();
-    v2.push("Hello".to_string());
-    v2.push(String::from("world"));
-    println!("dynamically built vector: {:?}", v2);
-    println!("first element: {}", v2[0]);
-    for el in &mut v2 {
-        *el += "xx";
-    }
-    for el in &v2 {
-        println!("{}", el);
-    }
-}
-
-fn test_hashmaps() {
-    let mut scores = HashMap::new();
-    scores.insert("john", 10);
-    scores.insert("mary", 20);
-
-    println!("scores: {:?}", scores);
-
-    // hash map with .collect()
-    let persons = vec![("homer", 42), ("marge", 30)];
-    let collect_scores: HashMap<_, _> = persons.into_iter().collect();
-    println!("collect_scores: {:?}", collect_scores);
-
-    for (p, s) in &collect_scores {
-        println!("person {}: score {}", p, s);
-    }
-
-    println!("john's score: {}", scores.get("john").unwrap());
-    println!("jake's score: {}", scores.get("jake").unwrap_or(&-1));
-
-    // double scores
-    for (_, v) in scores.iter_mut() {
-        *v *= 2;
-    }
-    println!("scores after doubling: {:?}", scores);
-
-    // double scores of immutable hashmap (rebuild it)
-    let collect_scores: HashMap<_, _> = collect_scores.into_iter()
-        .map(|(k, v)| (k, 2 * v))
-        .collect();
-    println!("collect_scores after rebuilding with doubling: {:?}", collect_scores);
-}
-
-fn test_files() {
-    if let Ok(mut f) = File::open("Cargo.toml") {
-        let mut contents = String::new();
-        match f.read_to_string(&mut contents) {
-            Ok(len) => println!("successfully opened Cargo.toml: {:?}, contents {} bytes:\n{}\n----------", f, len, contents),
-            Err(e) => panic!("could not read file: {:?}", e)
-        }
-    } else {
-        println!("could not open Cargo.toml");
-    }
-
-    // alternative form, more specific error checking
-    let mut f = File::open("Cargo.toml").unwrap_or_else(|e| {
-        if e.kind() == ErrorKind::NotFound {
-            println!("Cargo.toml not found, falling back to /dev/null");
-            // need to return a File
-            File::open("/dev/null").unwrap()
-        } else {
-            panic!("Could not open Cargo.toml: {:?}", e);
-        }
-    });
-    let mut contents = String::new();
-    let len = f.read_to_string(&mut contents).unwrap_or_else(|e| {
-        panic!("Could not read file: {:?}", e);
-    });
-    println!("successfully opened Cargo.toml with unwrap_or_else: {:?}, contents {} bytes:\n{}\n----------", f, len, contents);
-
-    // using the '?' operator
-    match read_file("Cargo.toml") {
-        Ok(s) => println!("Cargo.toml contents:\n{}\n-------------", s),
-        Err(e) => println!("Could not open Cargo.toml: {:?}", e)
-    }
-
-    // using std API
-    match fs::read_to_string("Cargo.toml") {
-        Ok(s) => println!("Cargo.toml contents:\n{}\n-------------", s),
-        Err(e) => println!("Could not open Cargo.toml: {:?}", e)
-    }
-}
-
-fn test_generics() {
-    let num_list = vec![3, 42, -7, 100, 0];
-    println!("largest number: {}", largest(&num_list));
-    println!("num_list: {:?}", num_list);
-
-    let char_list = vec!['a', 'y', 'q', 'm'];
-    println!("largest char: {}", largest(&char_list));
-
-    let str_list = vec!["hello", "world", "blue", "planet"];
-    println!("largest str: {}", largest(&str_list));
-    println!("str_list: {:?}", str_list);
-
-    let string_list = vec!["aaaa".to_string(), "xxxxx".to_string(), "ffff".to_string()];
-    println!("largest string (with cloning): {}", largest_clone(&string_list));
-    println!("largest string (with ref): {}", largest_ref(&string_list));
-    println!("string_list: {:?}", string_list);
-
-    let s1 = String::from("abcd");
-    let l;
-    {
-        let s2 = "efghi";
-        l = longest(&s1, s2);
-    }
-    println!("longest string: {}", l);
-}
-
-fn test_closures() {
-    let mut expensive_int_result = Cacher::new(|x| {
-        println!("calculating expensive int result for {}", x);
-        2 * x
-    });
-
-    println!("1st int call for value 1: {}", expensive_int_result.value(1));
-    println!("2nd int call for value 1: {}", expensive_int_result.value(1));
-    println!("1st int call for value 2: {}", expensive_int_result.value(2));
-
-    let mut expensive_str_result = Cacher::new(|x: &str| {
-        println!("calculating expensive str result for {}", x);
-        x.len()
-    });
-
-    println!("1st int call for value abc: {}", expensive_str_result.value("abc"));
-    println!("2nd int call for value abc: {}", expensive_str_result.value("abc"));
-    println!("1st int call for value defg: {}", expensive_str_result.value("defg"));
-}
-
-fn test_iterators() {
-    let v1 = vec!["Hello", "good", "world"];
-    // implied default is .into_iter() which consumes v1
-    for s in v1.iter() {
-        println!("element: {}", s);
-    }
-    // can still use it now
-    println!("v1: {:?}", &v1);
-
-    // manual iteration
-    let mut v1_iter = v1.iter();
-    while let Some(e) = v1_iter.next() {
-        println!("while loop over iter: {}", e);
-    }
-
-    for l_element in v1.iter().filter(|x| x.contains('l')) {
-        println!("v1 element containing 'l': {}", l_element);
-    }
-
-    let v2 = vec![1, 2, 3];
-    let double_v2: Vec<_> = v2.iter().map(|x| x * 2).collect();
-    println!("doubled v2: {:?}", double_v2);
-
-    for i in v2.into_iter().map(|x| x * 3) {
-        println!("for loop triplicating v2: {}", i);
-    }
-
-    for i in Counter5::new() {
-        println!("Counter 5 value: {}", i);
-    }
-}
-
-fn main() {
-    test_strings();
-    test_vectors();
-    test_hashmaps();
-    test_files();
-    test_generics();
-    test_closures();
-    test_iterators();
-}
diff --git a/src/word_utils.rs b/src/word_utils.rs
deleted file mode 100644
index e3e71bf..0000000
--- a/src/word_utils.rs
+++ /dev/null
@@ -1,43 +0,0 @@
-pub fn first_word(s: &str) -> &str {
-    for (i, &item) in s.as_bytes().iter().enumerate() {
-        if item == b' ' {
-            return &s[..i];
-        }
-    }
-
-    s
-}
-
-pub fn second_word(s: &str) -> Option<&str> {
-    for (i, &item) in s.as_bytes().iter().enumerate() {
-        if item == b' ' {
-            return Some(first_word(&s[(i + 1)..]));
-        }
-    }
-
-    None
-}
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-
-    #[test]
-    fn test_first_word() {
-        assert_eq!(first_word(""), "");
-        assert_eq!(first_word("one"), "one");
-        assert_eq!(first_word("one two"), "one");
-
-        assert_eq!(first_word(&String::from("one two")), "one");
-    }
-
-    #[test]
-    fn test_second_word() {
-        assert_eq!(second_word(""), None);
-        assert_eq!(second_word("one"), None);
-        assert_eq!(second_word("one two"), Some("two"));
-        assert_eq!(second_word("one two three"), Some("two"));
-
-        assert_eq!(second_word(&String::from("one two three")), Some("two"));
-    }
-}
diff --git a/tests/test_lib.rs b/tests/test_lib.rs
deleted file mode 100644
index af9bbe2..0000000
--- a/tests/test_lib.rs
+++ /dev/null
@@ -1,51 +0,0 @@
-#[macro_use]
-extern crate global_counter;
-
-use learning::*;
-
-#[test]
-fn test_longest() {
-    assert_eq!(longest("abc", "de"), "abc");
-    assert_eq!(longest("abc", "def"), "def");
-    assert_eq!(longest("abc", "defg"), "defg");
-}
-
-#[test]
-fn test_cacher_int_int() {
-    global_default_counter!(CALLED, u32);
-    let mut cacher = Cacher::new(|x| {
-        CALLED.inc();
-        2 * x
-    });
-    assert_eq!(cacher.value(1), 2);
-    assert_eq!(CALLED.get_cloned(), 1);
-    // second time cached
-    assert_eq!(cacher.value(1), 2);
-    assert_eq!(CALLED.get_cloned(), 1);
-    // re-evaluated for new value
-    assert_eq!(cacher.value(-2), -4);
-    assert_eq!(CALLED.get_cloned(), 2);
-    // old arg still cached
-    assert_eq!(cacher.value(1), 2);
-    assert_eq!(CALLED.get_cloned(), 2);
-}
-
-#[test]
-fn test_cacher_str_usize() {
-    global_default_counter!(CALLED, u32);
-    let mut cacher = Cacher::new(|x: &str| {
-        CALLED.inc();
-        x.len()
-    });
-    assert_eq!(cacher.value("abc"), 3);
-    assert_eq!(CALLED.get_cloned(), 1);
-    // second time cached
-    assert_eq!(cacher.value("abc"), 3);
-    assert_eq!(CALLED.get_cloned(), 1);
-    // re-evaluated for new value
-    assert_eq!(cacher.value("defg"), 4);
-    assert_eq!(CALLED.get_cloned(), 2);
-    // old arg still cached
-    assert_eq!(cacher.value("abc"), 3);
-    assert_eq!(CALLED.get_cloned(), 2);
-}