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historyReverser & array reverse

"use strict";

/**
 *
 * @author xgqfrms
 * @license MIT
 * @copyright xgqfrms
 *
 * @description historyReverser
 * @augments Reverse 逆向 / Recursive 递归
 * @example
 * @link
 *
 */

const historyReverser = (datas = [], text = ``, debug = false) => {
    let result = {};
    let newDatas = [];
    let reverseDatas = [];
    let length = datas.length;
    if (length === 10) {
        if(datas.includes(text)) {
            // remove old & add new
            let index = datas.indexOf(text);
            datas.splice(index, 1);
            datas.push(text);
        } else {
            // add new
            datas.push(text);
            datas.shift(0);
        }
    } else {
        datas.push(text);
    }
    newDatas = datas;
    datas.forEach(
        (item, i) => {
            let value = datas[length - i - 1];
            reverseDatas.push(value);
        }
    );
    result = {
        newDatas,
        reverseDatas,
    };
    return result;
};


export default historyReverser;

export {
    historyReverser,
};

tesing

let datas = ["1", "2", "3", "4", "5", "6", "7", "8", "9", "10"]

let text = "5";
// let text = "15";
const historyReverser = (datas = [], text = ``, debug = false) => {
    let result = {};
    let newDatas = [];
    let reverseDatas = [];
    let length = datas.length;
    if (length === 10) {
        if(datas.includes(text)) {
            // remove old & add new
            let index = datas.indexOf(text);
            datas.splice(index, 1);
            datas.push(text);
        } else {
            // add new
            datas.push(text);
            datas.shift(0);
        }
    } else {
        datas.push(text);
    }
    newDatas = datas;
    datas.forEach(
        (item, i) => {
            let value = datas[length - i - 1];
            reverseDatas.push(value);
        }
    );
    result = {
        newDatas,
        reverseDatas,
    };
    return result;
};

let ReverseArray = historyReverser(datas, text);

console.log(`ReverseArray =`, ReverseArray);

MDN & Array

https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array

0.push

1. shift

2. unshift

3. slice

4. splice

5. includes
   6.infdexOf
   7.last​IndexOf

---

bug

"use strict";

/**
 *
 * @author xgqfrms
 * @license MIT
 * @copyright xgqfrms
 *
 * @description historyReverser
 * @augments Reverse 逆向 / Recursive 递归
 * @example
 * @link
 *
 */

const historyReverser = (datas = [], text = ``, debug = false) => {
    if (text === null) {
        text = `xyz`;
    }
    let result = {};
    let newDatas = [];
    let reverseDatas = [];
    let length = datas.length;
    if (length === 10) {
        if(datas.includes(text)) {
            // remove old & add new
            let index = datas.indexOf(text);
            datas.splice(index, 1);
            datas.push(text);
        } else {
            // add new
            datas.push(text);
            datas.shift(0);
        }
        if(datas.includes(text)) {
            // remove old & add new
            let index = datas.indexOf(text);
            datas.splice(index, 1);
            datas.push(text);
        } else {
            // add new
            datas.push(text);
            datas.shift(0);
        }
    } else {
        datas.push(text);
    }
    newDatas = datas;
    // datas.forEach(
    //     (item, i) => {
    //         let value = datas[length - i - 1];
    //         console.log(`null value`, value);
    //         reverseDatas.push(value);
    //     }
    // );
    if (1 <= length) {
        datas.forEach(
            (item, i) => {
                let value = datas[length - i - 1];
                console.log(`null value`, value);
                reverseDatas.push(value);
            }
        );
    } else {
        reverseDatas = datas;
    }
    result = {
        newDatas,
        reverseDatas,
    };
    return result;
};


export default historyReverser;

export {
    historyReverser,
};

---

OK

unshfit

"use strict";

/**
 *
 * @author xgqfrms
 * @license MIT
 * @copyright xgqfrms
 *
 * @description historyReverser
 * @augments Reverse 逆向 / Recursive 递归
 * @example
 * @link
 *
 */

const historyReverser = (datas = [], text = ``, debug = false) => {
    // console.log(`datas =`, datas);
    // console.log(`text =`, text);
    let result = {};
    let newDatas = [];
    let reverseDatas = [];
    let length = datas.length;
    // if(datas.indexOf(text) !== -1) {
    if(datas.includes(text)) {
        // remove old & add new
        let index = datas.indexOf(text);
        datas.splice(index, 1);
        console.log(`datas =`, datas);
        datas.unshift(text);
        // datas.push(text);
    } else {
        // add new
        if (length === 10) {
            datas.splice(9, 1);
            datas.unshift(text);
            // datas.push(text);
            // datas.shift(0);
        } else {
            // add new
            datas.unshift(text);
            // datas.push(text);
        }
    }
    newDatas = datas;
    reverseDatas = datas;
    // let new_length = newDatas.length;
    // if (1 <= new_length) {
    //     let temp = datas;
    //     reverseDatas = temp.reverse();
    //     // datas.forEach(
    //     //     (item, i) => {
    //     //         let value = datas[new_length - i - 1];
    //     //         // console.log(`value`, value);
    //     //         reverseDatas.push(value);
    //     //     }
    //     // );
    // } else {
    //     reverseDatas = datas;
    // }
    result = {
        newDatas,
        reverseDatas,
    };
    return result;
};


export default historyReverser;

export {
    historyReverser,
};

---