Javascript中的三个点

请告诉我下面代码中的3点是什么意思

在

const V=[…V1，…V2，…V3]的情况下很明显，新数组是从V1、V2、V3的所有元素创建的

在

…CreateTransfromStateandSymbols（V1，targetStates[0]）的情况下，

完全令人困惑

函数

createTransitionsFromStateAndSymbols

中的3个点也令人困惑

谢谢大家!

const FSM = require('./FSM');

const createTransitionsFromStateAndSymbols = (symbols, targetState) => symbols.reduce((acc, curValue) => ({
    ...acc,
    [curValue]: targetState,
}), {});

const createTargetTransitions = (targetStates) => ({
    ...createTransitionsFromStateAndSymbols(V1, targetStates[0]),
    ...createTransitionsFromStateAndSymbols(V2, targetStates[1]),
    ...createTransitionsFromStateAndSymbols(V3, targetStates[2])
})

const V1 = 'qazwsxedcrfvtgbyhnujmikolp'.split('');
const V2 =  '!@#$%^&*()'.split('');
const V3 = '0123456789'.split('');

const V = [...V1, ...V2, ...V3];

const Q = ['q0', 'q1', 'q2', 'q3', 'q4', 'q5', 'q6', 'q7', 'q8', 'q9', 'q10']

const S = 'q0';

const F = ['q10'];

const transitions = {
    q0: createTargetTransitions(['q1', 'q4', 'q7']),
    q1: createTargetTransitions(['q1', 'q2', 'q3']),
    q2: createTargetTransitions(['q2', 'q2', 'q10']),
    q3: createTargetTransitions(['q3', 'q10', 'q3']),
    q4: createTargetTransitions(['q5', 'q4', 'q6']),
    q5: createTargetTransitions(['q5', 'q5', 'q10']),
    q6: createTargetTransitions(['q10', 'q6', 'q6']),
    q7: createTargetTransitions(['q8', 'q9', 'q7']),
    q8: createTargetTransitions(['q8', 'q10', 'q8']),
    q9: createTargetTransitions(['q10', 'q9', 'q9']),
    q10: createTargetTransitions(['q10', 'q10', 'q10']),
};

const fsm = new FSM(V, Q, S, F, transitions);

const startTime = +(new Date());
console.log(fsm.test('123qasda')) //false
const endTime = +(new Date());

console.log(endTime - startTime)

---

你也可以在谷歌上搜索“Javascript中的三个点”B什么是“完全令人困惑的”？如果你在谷歌上搜索你的确切标题“Javascript中的三个点”，您已经获得了相关的搜索词。下一步将是简单地阅读文档；文档中包含一些简单的示例，您可以在浏览器控制台中尝试。如果在所有这些之后有什么让您感到困惑，请具体询问。

class FSM {
    /**
     * 
     * @param {String[]} alphbet 
     * @param {String[]} states 
     * @param {String} startState 
     * @param {String[]} finiteStates 
     * @param {Object} transitions 
     */
    constructor(alphbet, states, startState, finiteStates, transitions) {
        this.alphbet = alphbet;
        this.states = states;
        this.currentState = startState;
        this.finiteStates = finiteStates;
        this.transitions = transitions;
    }

    _checkExistTransition(state, symbol) {
        return (this.transitions[state] && this.transitions[state][symbol]);
    }

    _changeState(symbol) {
        if (this._checkExistTransition(this.currentState, symbol)) {
            this.currentState = this.transitions[this.currentState][symbol];
        } else {
            throw new Error(`No transitions from ${this.currentState} by ${symbol}`);
        }
    }

    _checkBelogAlphabet(symbol) {
        if (this.alphbet.includes(symbol)) {
            return true;
        } else {
            throw new Error(`Unknown symbol ${symbol}`);
        }
    }

    test(value) {
        for (let symbol of value) {
            this._checkBelogAlphabet(symbol);
            this._changeState(symbol);
        }

        return this.finiteStates.includes(this.currentState);
    }
}

module.exports = FSM;