Building for iOS I am now getting the same error without the webpack message:
ionic cordova emulate ios
Running app-scripts build: --address 0.0.0.0 --port 8100 --p 8100 --livereload-port 35729 --r 35729 --iscordovaserve --nobrowser
[19:21:38] build dev started ...
[19:21:38] clean started ...
[19:21:38] clean finished in 7 ms
[19:21:38] copy started ...
[19:21:38] transpile started ...
[19:21:45] transpile finished in 7.45 s
[19:21:45] preprocess started ...
[19:21:45] deeplinks started ...
[19:21:46] deeplinks finished in 377 ms
[19:21:46] preprocess finished in 379 ms
[19:21:46] webpack started ...
[19:21:46] copy finished in 8.27 s
[19:22:00] webpack finished in 14.16 s
[19:22:00] sass started ...
[19:22:02] sass finished in 2.02 s
[19:22:02] postprocess started ...
[19:22:02] postprocess finished in 9 ms
[19:22:02] lint started ...
[19:22:02] build dev finished in 24.17 s
> ionic cordova prepare
> cordova prepare
✔ Running command - done!
> cordova emulate ios
TypeError: ctx.sourceFile.getLineEndOfPosition is not a function
at isEntireLine (/Users/me/Documents/Typescript/app/node_modules/tslint/lib/rules/noUnusedVariableRule.js:217:32)
at removeAll (/Users/me/Documents/Typescript/app/node_modules/tslint/lib/rules/noUnusedVariableRule.js:209:17)
at /Users/me/Documents/Typescript/app/node_modules/tslint/lib/rules/noUnusedVariableRule.js:164:13
at /Users/me/Documents/Typescript/app/node_modules/tslint/lib/rules/noUnusedVariableRule.js:285:23
at visitEachNode (/Users/me/Documents/Typescript/app/node_modules/typescript/lib/typescript.js:8338:30)
at Object.forEachChild (/Users/me/Documents/Typescript/app/node_modules/typescript/lib/typescript.js:8498:24)
at forEachImport (/Users/me/Documents/Typescript/app/node_modules/tslint/lib/rules/noUnusedVariableRule.js:283:15)
at addImportSpecifierFailures (/Users/me/Documents/Typescript/app/node_modules/tslint/lib/rules/noUnusedVariableRule.js:139:5)
at walk (/Users/me/Documents/Typescript/app/node_modules/tslint/lib/rules/noUnusedVariableRule.js:130:9)
at /Users/me/Documents/Typescript/app/node_modules/tslint/lib/rules/noUnusedVariableRule.js:38:75
[19:22:07] lint finished in 5.11 s
Building project: /Users/me/Documents/Typescript/app/platforms/ios/app.xcworkspace
Configuration: Debug