How to resolve “core_1.PriorityQueue is not a constructor” in angular when creating a component or module

If you are generating angular component or module from angular cli using command ng g m [module name] and you get the error trace as below

TypeError: core_1.PriorityQueue is not a constructor
at new TaskScheduler (E:\angularapp\node_modules\@angular-devkit\schematics\src\engine\task.js:20:23)
at SchematicEngine.createContext (E:\angularapp\node_modules\@angular-devkit\schematics\src\engine\engine.js:81:31)
at SchematicImpl.call (E:\angularapp\node_modules\@angular-devkit\schematics\src\engine\schematic.js:35:38)
at Promise (E:\angularapp\node_modules\@angular\cli\tasks\schematic-run.js:73:23)
at new Promise (<anonymous>)
at Class.run (E:\angularapp\node_modules\@angular\cli\tasks\schematic-run.js:72:16)
at Class.run (E:\angularapp\node_modules\@angular\cli\commands\generate.js:152:33)
at resolve (E:\angularapp\node_modules\@angular\cli\ember-cli\lib\models\command.js:261:20)
at new Promise (<anonymous>)
at Class.validateAndRun (E:\angularapp\node_modules\@angular\cli\ember-cli\lib\models\command.js:240:12)

Then you are at the right location.

Solution
Open the package.json file of your application and search forĀ angular-devkit/core dependency under devDependencies tag. It will look something like this.

“devDependencies”: {
“@angular-devkit/core”: “0.0.28”,
}

Error trace above is telling you that the angular-devkit/core version has gone older. Just update it to the latest version by running below command.

npm i @angular-devkit/core@latest

where i is the short-cut to install.
This will update the angular-devkit/core version. You can go and verify the version update in your package.json file. Now if you try to generate a component or module, it will be successfully generated without any errors.
Note that if you cannot update angular-devkit/core to the latest version, then update it to some higher version than the current version of your application using command

npm i @angular-devkit/core@0.0.029

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