Struct comparer::HashMapComparer

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pub struct HashMapComparer<K: Clone + Eq + Hash, V: Clone + PartialEq> { /* private fields */ }

Expand description

HashMapC

Implementations§

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impl<K: Clone + Eq + Hash, V: Clone + PartialEq> HashMapComparer<K, V>

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pub fn new() -> Self

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pub fn clone_last(&self) -> HashMap<K, V>

Clones last hashmap

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pub fn is_same(&self, comparable: &HashMap<K, V>) -> bool

Checks if last hashmap is the same as new one

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pub fn update(&self, new_map: &HashMap<K, V>)

Updates last hashmap to a new value

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pub fn is_same_update(&self, new_map: &HashMap<K, V>) -> bool

Checks if last hashmap is the same as new one and updates it to be that new value

§Examples

  use std::collections::HashMap;
  use comparer::HashMapComparer;

  let mut my_hashmap = HashMap::<u8, &str>::new();
  let comparer = HashMapComparer::<u8, &str>::new();
  my_hashmap.insert(1, "foo");
  // HashMap has new values
  assert_eq!(false, comparer.is_same_update(&my_hashmap));
  // Hashmap has not recived new values
  assert_eq!(true, comparer.is_same_update(&my_hashmap));

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pub fn update_and_compare( &self, new_map: &HashMap<K, V>, ) -> Result<HashMap<K, V>, PoisonError<K>>

Updates last hashmap, compares new one to the last one and returns changed values. If you want to compare hashmap without updating last hashmap use compare(). If you want to update hashmap without comparing it use update() and if you want to return bool instead of changed values use is_same() or is_same_update().

§Examples

  use std::collections::HashMap;
  use comparer::HashMapComparer;
  let comparer = HashMapComparer::<u8, &str>::new();
  let mut my_hashmap = HashMap::<u8, &str>::new();
  my_hashmap.insert(1, "foo");
  my_hashmap.insert(2, "bar");
  my_hashmap.insert(4, "foo");
  let mut results: Vec<HashMap<u8, &str>> = vec![];
  for i in 0..5 {
      my_hashmap.insert(i, "foo");
      results.push(comparer.update_and_compare(&my_hashmap).unwrap());
  }
  assert_eq!(
      vec![
          // In a first comparison comparer always returns whole hashmap because all values in it is new
          HashMap::<u8, &str>::from_iter(vec![(0, "foo"), (4, "foo"), (2, "bar"), (1, "foo")]),
          // Returns empty hashmap because value 1: "foo" didn't change
          HashMap::<u8, &str>::new(),
          // Returns hashmap with 2: "foo" because it was changed from 2: "bar"
          HashMap::<u8, &str>::from_iter(vec![(2, "foo")]),
          // Returns hashmap with 3: "foo" because it's a new value
          HashMap::<u8, &str>::from_iter(vec![(3, "foo")]),
           //Returns empty hashmap because value 4: "foo" didn't change
          HashMap::<u8, &str>::new(),
      ],
      results
  );