added comments to container_type

.idea/Rust-Programming.iml

@@ -6,9 +6,11 @@
       <sourceFolder url="file://$MODULE_DIR$/duplicates/src" isTestSource="false" />
       <sourceFolder url="file://$MODULE_DIR$/str_sort/src" isTestSource="false" />
       <sourceFolder url="file://$MODULE_DIR$/sparse_vector/src" isTestSource="false" />
+      <sourceFolder url="file://$MODULE_DIR$/container_type/src" isTestSource="false" />
       <excludeFolder url="file://$MODULE_DIR$/duplicates/target" />
       <excludeFolder url="file://$MODULE_DIR$/str_sort/target" />
       <excludeFolder url="file://$MODULE_DIR$/sparse_vector/target" />
+      <excludeFolder url="file://$MODULE_DIR$/container_type/target" />
     </content>
     <orderEntry type="inheritedJdk" />
     <orderEntry type="sourceFolder" forTests="false" />

container_type/src/main.rs

@@ -17,15 +17,35 @@ use std::{vec::{IntoIter}, ops::Index, ops::IndexMut, println};
  * Copyright (c) Sven Vogel
  */
 
+/// A vector based implementation of an associative map.
+/// This strucutre maps a given key to a single value.
+/// The type achives this by storing every pair of key/value pairs
+/// in a single vector.
+/// Thus for looking up a value takes a linear amount of time: O(n) in the worst case.
+/// Adding a new value is a constant time operation since the map is not sorted in any
+/// particular way.
+/// Note that it is not possible to insert a new value with the same key. Instead the old value
+/// associated with the already existing key will be replaced with the new value.
+/// # Example
+/// ```rust ignore
+/// let mut map = HashishMap::new();
+/// 
+/// map.insert("abc", 99);
+/// 
+/// map[&"abc"] += 1;
+/// ```
 pub struct HashishMap<K, V> where K: Eq {
     vec: Vec<(K, V)>
 }
 
 impl<K, V> HashishMap<K, V> where K: Eq {
+    /// Create a new empty instance
     pub fn new() -> Self {
         Self { vec: vec![] }
     }
 
+    /// retrieve a reference to value associated with the specified key
+    /// if no such key exists in the map [`Option::None`] is returned
     pub fn get(&self, key: &K) -> Option<&V> {
         return match self.vec.iter().find(|(k, _)| *k == *key) {
             Some((_, v)) => Some(v),
@@ -33,6 +53,8 @@ impl<K, V> HashishMap<K, V> where K: Eq {
         }
     }
 
+    /// retrieve a mutable reference to value associated with the specified key
+    /// if no such key exists in the map [`Option::None`] is returned
     pub fn get_mut(&mut self, key: &K) -> Option<&mut V> {
         return match self.vec.iter_mut().find(|(k, _)| *k == *key) {
             Some((_, v)) => Some(v),
@@ -40,6 +62,9 @@ impl<K, V> HashishMap<K, V> where K: Eq {
         }
     }
 
+    /// insert a new value at the specified key.
+    /// Overrides the existing value if the key already exists.
+    /// The overriden value is discarded.
     pub fn insert(&mut self, key: K, value: V) {
         if let Some(val) = self.get_mut(&key) {
             *val = value;
@@ -48,6 +73,8 @@ impl<K, V> HashishMap<K, V> where K: Eq {
         }
     }
 
+    /// Removes the key/value pair with the specified key from the map and return the value of the pair.
+    /// If no such pair can be found, [`Option::None`] is retuned
     pub fn remove(&mut self, key: &K) -> Option<V> {
         // find a key matching the parameter and its according index.
         // remove the item at the found index from the vector and return its value
@@ -68,7 +95,6 @@ impl<K,V> Index<K> for HashishMap<K, V> where K: Eq {
     }
 }
 
-
 impl<K,V> IndexMut<K> for HashishMap<K, V> where K: Eq {
 
     fn index_mut(&mut self, index: K) -> &mut Self::Output {
@@ -101,5 +127,4 @@ fn main() {
     for (k, v) in guter_stoff {
         println!("({k}, {:x})", v);
     }
-
 }