功能“实时”组合(Functional “real-time” composition)

 我最近发现了一篇很棒的文章，内容涉及对象组合VS传统继承的好处。 
 
 希望我的问题不会被标记为自以为是，但我想知道在对象基于用户的游戏交互进行更改时使用合成的好方法。 
 
 以文章代码为例： 
 
const canCast = (state) => ({
    cast: (spell) => {
        console.log(`${state.name} casts ${spell}!`);
        state.mana--;
    }
})

const canFight = (state) => ({
    fight: () => {
        console.log(`${state.name} slashes at the foe!`);
        state.stamina--;
    }
})

const fighter = (name) => {
  let state = {
    name,
    health: 100,
    stamina: 100
  }

  return Object.assign(state, canFight(state));
}

const mage = (name) => {
  let state = {
    name,
    health: 100,
    mana: 100
  }

  return Object.assign(state, canCast(state));
}

scorcher = mage('Scorcher')
scorcher.cast('fireball');    // Scorcher casts fireball!
console.log(scorcher.mana)    // 99

slasher = fighter('Slasher')
slasher.fight();              // Slasher slashes at the foe!
console.log(slasher.stamina)  // 99
 
 如何在运行时使用组合来更改Character对象的状态？ 而不是已经存在的Mage对象，我希望Character对象基于游戏事件而改变，例如。 角色捡起一名工作人员，现在成为一名现在可以施法的“法师”。 我想到的第一件事就是在Character中有一个状态属性，它根据交互而变化，而Character则以某种方式“继承”现在施放并获得法术力状态属性的能力。 

I recently came across a great article covering the benefits of object composition VS traditional inheritance.
 
Hopefully my question is not going to be flagged as opinionated but I'd like to know a good approach to using composition for when an object changes based on a user's game interaction.
 
Using the articles code as an example: 
 
const canCast = (state) => ({
    cast: (spell) => {
        console.log(`${state.name} casts ${spell}!`);
        state.mana--;
    }
})

const canFight = (state) => ({
    fight: () => {
        console.log(`${state.name} slashes at the foe!`);
        state.stamina--;
    }
})

const fighter = (name) => {
  let state = {
    name,
    health: 100,
    stamina: 100
  }

  return Object.assign(state, canFight(state));
}

const mage = (name) => {
  let state = {
    name,
    health: 100,
    mana: 100
  }

  return Object.assign(state, canCast(state));
}

scorcher = mage('Scorcher')
scorcher.cast('fireball');    // Scorcher casts fireball!
console.log(scorcher.mana)    // 99

slasher = fighter('Slasher')
slasher.fight();              // Slasher slashes at the foe!
console.log(slasher.stamina)  // 99
 
How do I use composition to change the state of the Character object during run-time? Instead of the Mage object already existing I want the Character object to change based on a game event eg. Character picks up a staff and now becomes a "Mage" who can now Cast spells. First thing that comes to mind is to have a state property in Character that changes based on the interaction and the Character somehow "inherits" the ability to now Cast and gains a mana state property.

原文：https://stackoverflow.com/questions/50844719