Rustでコードをコピーしない方法

プログラミングにおけるマナーの最初のルール（または最初のルールの1つ）は、「コードをコピーしないでください」です。関数と継承を使用します。

関数ですべてが明確になりますが、継承はより複雑です。Rustには直接の継承がないことをおそらくご存知でしょうが、それに似たものを実現する方法はいくつかあります。それらについてお話しします。

impldynトレイト

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enum Damage{
    Physical(f32),
    Magic(f32)
}

trait Character{
  fn get_magic_resistance(&self) -> f32;
  fn get_physical_resistance(&self) -> f32;
  fn set_hp(&mut self, new_value: f32);
  fn get_hp(&self) -> f32;
  fn get_type(&self) -> CharacterType;
  fn get_dmg(&self) -> Damage;
}

impl dyn Character {
  fn make_hurt(&mut self, dmg: Damage) {
    match dmg{
      Damage::Physical(dmg) => self.set_hp(self.get_hp() - dmg / self.get_physical_resistance().exp()),
      Damage::Magic(dmg) => self.set_hp(self.get_hp() - dmg / self.get_magic_resistance().exp())
    }
  }
}

#[derive(Debug, Clone, Copy)]
enum CharacterType {
    Mage,
    Warrior,
    Rogue
}

impl Default for CharacterType {
    fn default() -> Self{
        CharacterType::Warrior
    }
}

#[derive(Default)]
struct Player{
    ty: CharacterType,
    phys_resist: f32,
    mag_resist: f32,
    hp: f32,
    dmg: f32
}

impl Player {
    pub fn new(ty: CharacterType, hp: f32, dmg: f32) -> Self {
        Self{ ty, hp, dmg, .. Default::default() }
    }
}

impl Character for Player{
    #[inline]
    fn get_magic_resistance(&self) -> f32 {
        self.mag_resist
    }
    
    #[inline]
    fn get_physical_resistance(&self) -> f32{
        self.phys_resist
    }
    
    #[inline]
    fn set_hp(&mut self, new_value: f32){
        self.hp = new_value;
    }
    
    #[inline]
    fn get_hp(&self) -> f32 {
        self.hp
    }
    
    #[inline]
    fn get_type(&self) -> CharacterType {
        self.ty
    }
    
    fn get_dmg(&self) -> Damage{
        match self.ty {
            CharacterType::Mage => Damage::Magic(self.dmg),
            _ => Damage::Physical(self.dmg)
        }
    }
}

struct EnemyWarrior{
    ty: CharacterType,
    phys_resist: f32,
    mag_resist: f32,
    hp: f32,
    dmg: f32
}

impl Default for EnemyWarrior {
    fn default() -> Self {
        Self{
            ty: CharacterType::Warrior,
            phys_resist: 0.,
            mag_resist: 0.,
            hp: 10.,
            dmg: 1.
        }
    }
}

impl Character for EnemyWarrior{
    #[inline]
    fn get_magic_resistance(&self) -> f32 {
        self.mag_resist
    }
    
    #[inline]
    fn get_physical_resistance(&self) -> f32{
        self.phys_resist
    }
    
    #[inline]
    fn set_hp(&mut self, new_value: f32){
        self.hp = new_value;
    }
    
    #[inline]
    fn get_hp(&self) -> f32 {
        self.hp
    }
    
    fn get_type(&self) -> CharacterType {
        CharacterType::Warrior
    }
    
    fn get_dmg(&self) -> Damage{
        match self.ty {
            CharacterType::Mage => Damage::Magic(self.dmg),
            _ => Damage::Physical(self.dmg)
        }
    }
}

fn main(){
    let mut player = Player::new(CharacterType::Warrior, 10., 1.);
    let mut enemy = EnemyWarrior::default();
    
    <dyn Character>::make_hurt(&mut enemy, player.get_dmg());
    println!("{}", enemy.get_hp());
}
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

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use std::ops::Deref;
use std::ops::DerefMut;

enum Damage{
    Physical(f32),
    Magic(f32)
}

#[derive(Default)]
struct Character{
    ty: CharacterType,
    phys_resist: f32,
    mag_resist: f32,
    hp: f32,
    dmg: f32
}

impl Character {
    #[inline]
    fn get_magic_resistance(&self) -> f32 {
        self.mag_resist
    }
    
    #[inline]
    fn get_physical_resistance(&self) -> f32{
        self.phys_resist
    }
    
    #[inline]
    fn set_hp(&mut self, new_value: f32){
        self.hp = new_value;
    }
    
    #[inline]
    fn get_hp(&self) -> f32 {
        self.hp
    }
    
    #[inline]
    fn get_type(&self) -> CharacterType {
        self.ty
    }
    
    fn get_dmg(&self) -> Damage{
        match self.ty {
            CharacterType::Mage => Damage::Magic(self.dmg),
            _ => Damage::Physical(self.dmg)
        }
    }

  fn make_hurt(&mut self, dmg: Damage) {
    match dmg{
      Damage::Physical(dmg) => self.set_hp(self.get_hp() - dmg / self.get_physical_resistance().exp()),
      Damage::Magic(dmg) => self.set_hp(self.get_hp() - dmg / self.get_magic_resistance().exp())
    }
  }
}


#[derive(Debug, Clone, Copy)]
enum CharacterType {
    Mage,
    Warrior,
    Rogue
}

impl Default for CharacterType {
    fn default() -> Self{
        CharacterType::Warrior
    }
}

#[derive(Default)]
struct Player(Character);

impl Player {
    pub fn new(ty: CharacterType, hp: f32, dmg: f32) -> Self {
        Self(Character{ ty, hp, dmg, .. Default::default() })
    }
}

impl Deref for Player {
    type Target = Character;
    
    #[inline]
    fn deref(&self) -> &Self::Target{
        &self.0
    }
}

impl DerefMut for Player {
    #[inline]
    fn deref_mut(&mut self) -> &mut Self::Target{
        &mut self.0
    }
}


struct EnemyWarrior(Character);

impl Default for EnemyWarrior {
    fn default() -> Self {
        Self(Character {
            ty: CharacterType::Warrior,
            phys_resist: 0.,
            mag_resist: 0.,
            hp: 10.,
            dmg: 1.
        })
    }
}

impl Deref for EnemyWarrior {
    type Target = Character;
    
    #[inline]
    fn deref(&self) -> &Self::Target{
        &self.0
    }
}

impl DerefMut for EnemyWarrior {
    #[inline]
    fn deref_mut(&mut self) -> &mut Self::Target{
        &mut self.0
    }
}

fn main(){
    let mut player = Player::new(CharacterType::Warrior, 10., 1.);
    let mut enemy = EnemyWarrior::default();
    
    enemy.make_hurt(player.get_dmg());
    println!("{}", enemy.get_hp());
}
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

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struct Child (Parent, ChildInner);

impl Child {
  pub fn get_some_field_from_inner(&self) -> &ChildInner::Field {
    &self.1.field
  }
}
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

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つまり、実際、私がこのトピックについて言いたかったことはすべてです。私は何かが足りないのですか？このトピックについても懸念がある場合は、コメントに書き込んでください。Rustで継承が不足しているのは私だけではないことを知りたいと思います。