टाइपरर: क्लास अपरिभाषित मान को फ़ंक्शन या शून्य नहीं है

Question

मुझे इन इकाइयों को बनाने का प्रयास करते समय निम्न त्रुटि मिल रही है।

TypeError: Class extends value undefined is not a function or null

मैं इस परिपत्र निर्भरता के साथ कुछ है यह सोचते हैं रहा हूँ, लेकिन कैसे यह है कि जब तालिका विरासत और कई रिश्तों को एक का उपयोग कर से बचा जाना माना जाता है?

यह BaseComic_1.BaseComic पर निम्नलिखित जावास्क्रिप्ट के बारे में शिकायत कर रहा है।

let Variant = class Variant extends BaseComic_1.BaseComic {

यहाँ पूरी फाइल है।

"use strict"; 
var __decorate = (this && this.__decorate) || function (decorators, target, key, desc) { 
    var c = arguments.length, r = c < 3 ? target : desc === null ? desc = Object.getOwnPropertyDescriptor(target, key) : desc, d; 
    if (typeof Reflect === "object" && typeof Reflect.decorate === "function") r = Reflect.decorate(decorators, target, key, desc); 
    else for (var i = decorators.length - 1; i >= 0; i--) if (d = decorators[i]) r = (c < 3 ? d(r) : c > 3 ? d(target, key, r) : d(target, key)) || r; 
    return c > 3 && r && Object.defineProperty(target, key, r), r; 
}; 
var __metadata = (this && this.__metadata) || function (k, v) { 
    if (typeof Reflect === "object" && typeof Reflect.metadata === "function") return Reflect.metadata(k, v); 
}; 
Object.defineProperty(exports, "__esModule", { value: true }); 
const typeorm_1 = require("typeorm"); 
const Comic_1 = require("./Comic"); 
const BaseComic_1 = require("./BaseComic"); 
let Variant = class Variant extends BaseComic_1.BaseComic { 
}; 
__decorate([ 
    typeorm_1.ManyToOne(type => Comic_1.Comic, comic => comic.variants), 
    __metadata("design:type", Comic_1.Comic) 
], Variant.prototype, "comic", void 0); 
Variant = __decorate([ 
    typeorm_1.ClassEntityChild() 
], Variant); 
exports.Variant = Variant; 
//# sourceMappingURL=Variant.js.map 

---

import {Entity, Column, PrimaryGeneratedColumn, OneToMany} from "typeorm"; 
import {Comic} from "./Comic"; 

@Entity() 
export class Series { 

    @PrimaryGeneratedColumn() 
    public id: number; 

    @Column("text", { 
     length: 30 
    }) 
    public copyright: string; 

    @Column("text", { 
     length: 100 
    }) 
    public attributionText: string; 

    @Column("text", { 
     length: 150 
    }) 
    public attributionHTML: string; 

    @Column("text", { 
     length: 50 
    }) 
    public etag: string; 

    @Column("text", { 
     length: 200 
    }) 
    public title: string; 

    @Column("text") 
    public description: string; 

    @Column("number", { 
     length: 4 
    }) 
    public startYear: number; 

    @Column("number", { 
     length: 4 
    }) 
    public endYear: number; 

    @Column("text", { 
     length: 20 
    }) 
    public rating: string; 

    @Column("text", { 
     length: 20 
    }) 
    public type: string; 

    @Column("text") 
    public thumbnail: string; 

    @OneToMany(type => Comic, comic => comic.series) 
    public comics: Array<Comic>; 
} 

---

import {Entity, TableInheritance, PrimaryGeneratedColumn, Column, ManyToOne, DiscriminatorColumn} from "typeorm"; 
import {Series} from "./Series"; 

@Entity() 
@TableInheritance("class-table") 
@DiscriminatorColumn({ name: "type", type: "string"}) 
export class BaseComic { 

    @PrimaryGeneratedColumn() 
    public id: number; 

    @Column("text", { 
     length: 30 
    }) 
    public copyright: string; 

    @Column("text", { 
     length: 100 
    }) 
    public attributionText: string; 

    @Column("text", { 
     length: 150 
    }) 
    public attributionHTML: string; 

    @Column("text", { 
     length: 50 
    }) 
    public etag: string; 

    @Column("text", { 
     length: 200 
    }) 
    public title: string; 

    @Column("int") 
    public issue: number; 

    @Column("text") 
    public variantDescription: string; 

    @Column("boolean") 
    public variant: boolean; 

    @Column("text") 
    public description: string; 

    @Column("int") 
    public pageCount: number; 

    @Column("date") 
    public onSaleDate: Date; 

    @Column("date") 
    public unlimitedDate: Date; 

    @Column("text") 
    public thumbnail: string; 

    @ManyToOne(type => Series, series => series.comics) 
    public series: Series; 
} 

---

import {OneToMany, ClassEntityChild} from "typeorm"; 
import {Variant} from "./Variant"; 
import {BaseComic} from "./BaseComic"; 

@ClassEntityChild() 
export class Comic extends BaseComic { 

    @OneToMany(type => Variant, variant => variant.comic) 
    public variants: Variant[]; 
} 

---

import {ManyToOne, ClassEntityChild} from "typeorm"; 
import {Comic} from "./Comic"; 
import {BaseComic} from "./BaseComic"; 

@ClassEntityChild() 
export class Variant extends BaseComic { 

    @ManyToOne(type => Comic, comic => comic.variants) 
    public comic: Comic; 
} 

Answer 1

मैं एक ही मुद्दा रहा था। यह पता चला कि मैं सर्कुलर रूप से कक्षाओं का आयात कर रहा था, जो स्पष्ट रूप से एक सीमा है।

this अन्य उत्तर