ng-bootstrap typeahead TypeError: Object(...) is not a function

I would like to use the angular bootstrap typeahead linkToTypeahead in an angular5 app. But I keep getting the following error(s):

ERROR TypeError: Object(...) is not a function at new NgbTypeahead (typeahead.js:52) at createClass (core.js:12449) at createDirectiveInstance (core.js:12284) at createViewNodes (core.js:13742) at callViewAction (core.js:14176) at execComponentViewsAction (core.js:14085) at createViewNodes (core.js:13770) at callViewAction (core.js:14176) at execComponentViewsAction (core.js:14085) at createViewNodes (core.js:13770) 

and also:

ERROR TypeError: Cannot read property 'instance' of undefined at nodeValue (core.js:11753) at Object.eval [as handleEvent] (NgbdTypeaheadBasic.html:9) at handleEvent (core.js:13547) at callWithDebugContext (core.js:15056) at Object.debugHandleEvent [as handleEvent] (core.js:14643) at dispatchEvent (core.js:9962) at eval (core.js:10587) at HTMLDocument.eval (platform-browser.js:2628) at ZoneDelegate.invokeTask (zone.js:421) at Object.onInvokeTask (core.js:4740) 

I copied the Simple Typeahead code from the website link.

My package.json file:

{ "name": "test-type-ahead", "version": "0.0.0", "license": "MIT", "scripts": { "ng": "ng", "start": "ng serve", "build": "ng build --prod", "test": "ng test", "lint": "ng lint", "e2e": "ng e2e" }, "private": true, "dependencies": { "@angular/animations": "^5.2.0", "@angular/common": "^5.2.0", "@angular/compiler": "^5.2.0", "@angular/core": "^5.2.0", "@angular/forms": "^5.2.0", "@angular/http": "^5.2.0", "@angular/platform-browser": "^5.2.0", "@angular/platform-browser-dynamic": "^5.2.0", "@angular/router": "^5.2.0", "@ng-bootstrap/ng-bootstrap": "^2.0.0-alpha.0", "bootstrap": "^4.1.0", "core-js": "^2.4.1", "rxjs": "^5.5.6", "zone.js": "^0.8.19" }, "devDependencies": { "@angular/cli": "~1.7.3", "@angular/compiler-cli": "^5.2.0", "@angular/language-service": "^5.2.0", "@types/jasmine": "~2.8.3", "@types/jasminewd2": "~2.0.2", "@types/node": "~6.0.60", "codelyzer": "^4.0.1", "jasmine-core": "~2.8.0", "jasmine-spec-reporter": "~4.2.1", "karma": "~2.0.0", "karma-chrome-launcher": "~2.2.0", "karma-coverage-istanbul-reporter": "^1.2.1", "karma-jasmine": "~1.1.0", "karma-jasmine-html-reporter": "^0.2.2", "protractor": "~5.1.2", "ts-node": "~4.1.0", "tslint": "~5.9.1", "typescript": "~2.5.3" } } What I have tried so far:

1. reinstalled node_modules with npm -- does not help
2. Started a brand new project with the angular CLI and tried out the code there -- does not help.

Any help is greatly appreciated!