Uncaught (in promise): TypeError: Cannot read property 'call' of undefined in ionic3

Question

I faced a problem that every time I change my code an error occured :

1) Uncaught (in promise): TypeError: Cannot read property 'call' of undefined => core.js

2)Cannot read property 'call' of undefined => module-loader.js

so i have to do "ionic serve" everytime i change the code to remove the error. so i waste lot of times. can anyone know what's the problem?

• ionic CLI 4.0.2
• ionic-angular: "3.9.2",
• angular/core: "5.0.0",

Answer 1

If you are running multiple ionic serve on same machine then this error can come.

Try close all CMD windows and then start new CMD in your project folder and then do ionic serve

Answer 2

Hope, deleting the node_modules from your project codebase and doing npm install again solves your problem. Keep Learning.

Answer 3

ctrl + c after yes after

ionic serve again

all will be fine it work for me

Answer 4

此错误通常是同时运行多个 ionic serve 的结果。