Why do I get “TypeError: Class extends value undefined is not a constructor or null” when trying to run...
0
I have a simple application that is imported from webpack. The imported project exports a class like this...
export class BaseApp{...}
import { BaseApp } from "./MyClass"
import OtherThing from "./Other"
....
export { BaseApp, OtherThing }
Next I try to extend it in another node/express project...
import { BaseApp } from "@mine/util";
export class FullApp extends BaseApp{... }
I get...
class FullApp extends _mine_util__WEBPACK_IMPORTED_MODULE_0__["BaseA
pp"]{
^
TypeError: Class extends value undefined is not a constructor or null
How do I extend a class I am importing from Webpack?
Update here is an example project that demonstrates the issue...
https://github.com/jrgleason/simple-webpack-node
node.js webpack ecmascript-6
asked Nov 20 at 21:34
JGleason
12910
|
show 3 more comments
0
I have a simple application that is imported from webpack. The imported project exports a class like this...
export class BaseApp{...}
import { BaseApp } from "./MyClass"
import OtherThing from "./Other"
....
export { BaseApp, OtherThing }
Next I try to extend it in another node/express project...
import { BaseApp } from "@mine/util";
export class FullApp extends BaseApp{... }
I get...
class FullApp extends _mine_util__WEBPACK_IMPORTED_MODULE_0__["BaseA
pp"]{
^
TypeError: Class extends value undefined is not a constructor or null
How do I extend a class I am importing from Webpack?
Update here is an example project that demonstrates the issue...
https://github.com/jrgleason/simple-webpack-node
node.js webpack ecmascript-6
asked Nov 20 at 21:34
JGleason
12910
1
You might not be importingBaseAppproperly. However, we wouldn't be able to tell without knowing how it is exported.
– Felix Kling
Nov 20 at 22:06
What do you mean I am showing you how it is exported? Do I need to show it another way like after Webpack?
– JGleason
Nov 21 at 13:57
If I use it inside the lib that it is declared it works fine. So the actual declaration is fine.
– JGleason
Nov 21 at 13:58
Your are not showing how./MyClassexports the class.
– Felix Kling
Nov 21 at 15:52
Yeah I am I added that at the top and even then It is working in non node projects so I don't get it. I will made a simple project I will add that...
– JGleason
Nov 21 at 15:55
|
show 3 more comments
0
0
0
I have a simple application that is imported from webpack. The imported project exports a class like this...
export class BaseApp{...}
import { BaseApp } from "./MyClass"
import OtherThing from "./Other"
....
export { BaseApp, OtherThing }
Next I try to extend it in another node/express project...
import { BaseApp } from "@mine/util";
export class FullApp extends BaseApp{... }
I get...
class FullApp extends _mine_util__WEBPACK_IMPORTED_MODULE_0__["BaseA
pp"]{
^
TypeError: Class extends value undefined is not a constructor or null
How do I extend a class I am importing from Webpack?
Update here is an example project that demonstrates the issue...
https://github.com/jrgleason/simple-webpack-node
node.js webpack ecmascript-6
asked Nov 20 at 21:34
JGleason
12910
I have a simple application that is imported from webpack. The imported project exports a class like this...
export class BaseApp{...}
import { BaseApp } from "./MyClass"
import OtherThing from "./Other"
....
export { BaseApp, OtherThing }
Next I try to extend it in another node/express project...
import { BaseApp } from "@mine/util";
export class FullApp extends BaseApp{... }
I get...
class FullApp extends _mine_util__WEBPACK_IMPORTED_MODULE_0__["BaseA
pp"]{
^
TypeError: Class extends value undefined is not a constructor or null
How do I extend a class I am importing from Webpack?
Update here is an example project that demonstrates the issue...
https://github.com/jrgleason/simple-webpack-node
node.js webpack ecmascript-6
node.js webpack ecmascript-6
asked Nov 20 at 21:34
JGleason
12910
asked Nov 20 at 21:34
JGleason
12910
edited Nov 21 at 17:28
asked Nov 20 at 21:34
JGleason
12910
asked Nov 20 at 21:34
JGleason
12910
asked Nov 20 at 21:34
JGleason
12910
12910
1
You might not be importingBaseAppproperly. However, we wouldn't be able to tell without knowing how it is exported.
– Felix Kling
Nov 20 at 22:06
What do you mean I am showing you how it is exported? Do I need to show it another way like after Webpack?
– JGleason
Nov 21 at 13:57
If I use it inside the lib that it is declared it works fine. So the actual declaration is fine.
– JGleason
Nov 21 at 13:58
Your are not showing how./MyClassexports the class.
– Felix Kling
Nov 21 at 15:52
Yeah I am I added that at the top and even then It is working in non node projects so I don't get it. I will made a simple project I will add that...
– JGleason
Nov 21 at 15:55
|
show 3 more comments
1
You might not be importingBaseAppproperly. However, we wouldn't be able to tell without knowing how it is exported.
– Felix Kling
Nov 20 at 22:06
What do you mean I am showing you how it is exported? Do I need to show it another way like after Webpack?
– JGleason
Nov 21 at 13:57
If I use it inside the lib that it is declared it works fine. So the actual declaration is fine.
– JGleason
Nov 21 at 13:58
Your are not showing how./MyClassexports the class.
– Felix Kling
Nov 21 at 15:52
Yeah I am I added that at the top and even then It is working in non node projects so I don't get it. I will made a simple project I will add that...
– JGleason
Nov 21 at 15:55
1
1
You might not be importing
BaseApp properly. However, we wouldn't be able to tell without knowing how it is exported.– Felix Kling
Nov 20 at 22:06
You might not be importing
BaseApp properly. However, we wouldn't be able to tell without knowing how it is exported.– Felix Kling
Nov 20 at 22:06
What do you mean I am showing you how it is exported? Do I need to show it another way like after Webpack?
– JGleason
Nov 21 at 13:57
What do you mean I am showing you how it is exported? Do I need to show it another way like after Webpack?
– JGleason
Nov 21 at 13:57
If I use it inside the lib that it is declared it works fine. So the actual declaration is fine.
– JGleason
Nov 21 at 13:58
If I use it inside the lib that it is declared it works fine. So the actual declaration is fine.
– JGleason
Nov 21 at 13:58
Your are not showing how
./MyClass exports the class.– Felix Kling
Nov 21 at 15:52
Your are not showing how
./MyClass exports the class.– Felix Kling
Nov 21 at 15:52
Yeah I am I added that at the top and even then It is working in non node projects so I don't get it. I will made a simple project I will add that...
– JGleason
Nov 21 at 15:55
Yeah I am I added that at the top and even then It is working in non node projects so I don't get it. I will made a simple project I will add that...
– JGleason
Nov 21 at 15:55
|
show 3 more comments
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1
You might not be importing
BaseAppproperly. However, we wouldn't be able to tell without knowing how it is exported.– Felix Kling
Nov 20 at 22:06
What do you mean I am showing you how it is exported? Do I need to show it another way like after Webpack?
– JGleason
Nov 21 at 13:57
If I use it inside the lib that it is declared it works fine. So the actual declaration is fine.
– JGleason
Nov 21 at 13:58
Your are not showing how
./MyClassexports the class.– Felix Kling
Nov 21 at 15:52
Yeah I am I added that at the top and even then It is working in non node projects so I don't get it. I will made a simple project I will add that...
– JGleason
Nov 21 at 15:55