vue中自定义filter的问题

Question

小白今天啃vuex，在网上看的文档，如下

getters: {
    openProjects: state => {
      return state.projects.filter(project => !project.completed)
    }
  }

这是vuex中的一段，我没看懂什么意思，filter不是过滤器吗？需要两个参数啊，这个怎么没有名字？
上下文代码如下，摆脱懂得帮忙讲一下。

import Vue from 'vue'
import Vuex from 'vuex'
import axios from 'axios'
Vue.use(Vuex)
const store = new Vuex.Store({
  state: {
    projects: []
  },
  actions: {
    LOAD_PROJECT_LIST: function ({ commit }) {
      axios.get('/secured/projects').then((response) => {
        commit('SET_PROJECT_LIST', { list: response.data })
      }, (err) => {
        console.log(err)
      })
    }
  },
  mutations: {
    SET_PROJECT_LIST: (state, { list }) => {
      state.projects = list
    }
  },
  getters: {
    openProjects: state => {
      return state.projects.filter(project => !project.completed)
    }
  }
})
export default store

Answer 1

此 filter 非彼 filter

https://developer.mozilla.org...