使用 find array 方法的 TypeScript 转译错误

typescript transpiling error with find array method

提问人:Gabriel Aquino 提问时间:12/17/2022 更新时间:12/18/2022 访问量:74

问:

我在 Typescript 中有这段代码

/**
 * Team information
 */
export class Team {    
    constructor( public name: string ) {}
}

/**
 * Half side of each match, with team and score of the team
 */
export class SideMatch {
    constructor( public team: Team, public score: number) {}
}

/**
 * Two side matches, that represents the match itself
 */
export class Match {
    constructor( private game: SideMatch[] ) { }

    addScore(team: number, goal: number) {
        this.game[team].score += goal;
    }

    winner() : number {
        if( this.game[0].score > this.game[1].score )
            return 0;
        if( this.game[0].score < this.game[1].score )
            return 1;            
        return -1;            
    }

    getGame() {
        return this.game;
    }

    toString() {
        console.log( `${this.game[0].team.name} ${this.game[0].score} vs ${this.game[1].score} ${this.game[1].team.name}` );        
    }
}

/**
 * Team stats, with points, (todo: victories, draws, loses, goals forward, goals against, goals difference)
 */
export class TeamStats {

    constructor(public team: Team, public point: number) {}
}

export class Tournament {
    private teams: Team[] = [];
    private table: TeamStats[] = [];
    private fixtures: Match[] = [];

    constructor() {}

    public addTeam(teamName: string) {
        let team: Team = new Team(teamName);
        this.teams.push(team);
        console.log(this.teams);
        
        let teamStats = new TeamStats(team, 0);
        this.table.push(teamStats);
    }

    /**
     * Get the team
     * #question how to return only the Team type? It's requiring to define undefined
     * @param teamName 
     * @returns 
     */
    public getTeam(teamName :string) : Team {
        try {
            //let teamFound = new Team('temp');
            const teamFound = this.teams.find(t => t.name = teamName);
            console.log(`team found ${teamFound.name}`);
            
            if (teamFound === undefined) {
                throw new TypeError('The value was promised to always be there!');
              }
            return teamFound;   
        } catch (error) {
            throw error;
        }
            
    }

    public addMatch(team1: Team, team2: Team) {
        let sideMatch1: SideMatch = new SideMatch(team1, 0);
        let sideMatch2: SideMatch = new SideMatch(team2, 0);
        console.log(`add match - sm1 ${sideMatch1.team.name}` );
        console.log(`add match - sm2 ${sideMatch2.team.name}` );
        var game1: SideMatch[] = [];

        game1.push(sideMatch1);
        game1.push(sideMatch2);
        console.log(game1);
        
        let match1 = new Match( game1 );

        this.fixtures.push(match1);
    }

    public addMatchResults(matchIndex: number, score1: number, score2: number) {
        this.fixtures[matchIndex].addScore(0, score1);
        this.fixtures[matchIndex].addScore(1, score2);
        this.calculateMatchPoints(matchIndex);
    }

    private calculateMatchPoints(matchIndex: number) {
        let results : number = this.fixtures[matchIndex].winner();
        console.log(results);
        
        if (results !== -1)
        {
            console.log(this.fixtures[matchIndex].getGame());             
        }       
        
    }

    public getMatch(index: number) : Match {
        return this.fixtures[index];
    }

}

当我尝试在 CLI 中转译我的代码时

tsc src/compile.ts

它显示以下错误:

D:\src\myApps\worldcup>tsc src/console
src/console.ts:80:42 - error TS2550: Property 'find' does not exist on type 'Team[]'. Do you need to change your target library? Try changing the 'lib' compiler option
 to 'es2015' or later.

80             const teamFound = this.teams.find(t => t.name = teamName);
                                            ~~~~


Found 1 error in src/console.ts:80

因此,我包含了具有以下设置的tsconfig.json:

{
  "compileOnSave": false,
  "compilerOptions": {
    "strictNullChecks": false,
   "lib": [
      "es2020",
      "dom",
    ]
  },  
}

现在我有两个问题:

  1. 我不能只使用 tsc src/console.ts 进行转译。我现在需要使用 tsc -b。为什么?

  2. 当我使用这些运行代码时,当我直接使用 getTeam 以及将 getTeam 方法的结果分配给变量时,会发生一些奇怪的事情:

let worldCup2022: Tournament = new Tournament();

worldCup2022.addTeam('Brazil');
worldCup2022.addTeam('Canada');
console.log('t1 name with getTeam ' + worldCup2022.getTeam('Canada').name); // shows correctly t1 name Canada
console.log('t2 name with getTeam ' + worldCup2022.getTeam('Brazil').name); // shows correctly t2 name Brazil
const team1 = worldCup2022.getTeam('Canada');  
const team2 = worldCup2022.getTeam('Brazil');
console.log('t1 name ' + team1.name); // shows incorrectly t1 name as Brazil (last one got)
console.log('t2 name ' + team2.name); // shows incorrectly t1 name as Brazil (last one got)
TypeScript 对象 OOP 按引用传递 译器

评论

0赞 Sandil Ranasinghe 12/18/2022
看看这个 stackoverflow.com/questions/40545329/... .

答:

1赞 Thomas Graham 12/18/2022 #1

TSC问题

您是否在根文件夹中运行了 tsc -init?这将初始化一个 tsconfig 文件,然后您可以运行

TSC公司

它将在根目录中编译所有内容。我的项目结构是这样的:

文件结构

团队名称问题

寻找团队的问题是你正在检查与 = in 相同的类型

const teamFound = this.teams.find((t) => (t.name = teamName));

当您真正想要比较该值时:

const teamFound = this.teams.find((t) => (t.name === teamName));

= vs == 与 ===

评论

0赞 Gabriel Aquino 12/18/2022
太棒了,托马斯!我不可能注意到这一点。从不!这在 JS 中非常棘手。在其他语言中,这种错误甚至不会编译,或者 IDE 会建议我修复。