With an updated npm, ionic app-script and same piece of codes it’s working all fine for me 
Sorry I don’t have any other ideas
My stack:
syntaxError@http://localhost:8100/build/vendor.js:133931:34 CompileMetadataResolver.prototype._getDependenciesMetadata@http://localhost:8100/build/vendor.js:149011:35 CompileMetadataResolver.prototype._getTypeMetadata@http://localhost:8100/build/vendor.js:148846:21 CompileMetadataResolver.prototype.getNonNormalizedDirectiveMetadata@http://localhost:8100/build/vendor.js:148354:19 CompileMetadataResolver.prototype._getEntryComponentMetadata@http://localhost:8100/build/vendor.js:149159:40 CompileMetadataResolver.prototype._getEntryComponentsFromProvider/<@http://localhost:8100/build/vendor.js:149140:42 CompileMetadataResolver.prototype._getEntryComponentsFromProvider@http://localhost:8100/build/vendor.js:149139:9 CompileMetadataResolver.prototype._getProvidersMetadata/<@http://localhost:8100/build/vendor.js:149094:77 CompileMetadataResolver.prototype._getProvidersMetadata@http://localhost:8100/build/vendor.js:149057:9 CompileMetadataResolver.prototype._getProvidersMetadata/<@http://localhost:8100/build/vendor.js:149059:17 CompileMetadataResolver.prototype._getProvidersMetadata@http://localhost:8100/build/vendor.js:149057:9 CompileMetadataResolver.prototype.getNgModuleMetadata/<@http://localhost:8100/build/vendor.js:148545:57 CompileMetadataResolver.prototype.getNgModuleMetadata@http://localhost:8100/build/vendor.js:148536:13 JitCompiler.prototype._loadModules@http://localhost:8100/build/vendor.js:166951:64 JitCompiler.prototype._compileModuleAndComponents@http://localhost:8100/build/vendor.js:166912:31 JitCompiler.prototype.compileModuleAsync@http://localhost:8100/build/vendor.js:166828:32 CompilerImpl.prototype.compileModuleAsync@http://localhost:8100/build/vendor.js:132767:34 PlatformRef.prototype.bootstrapModule@http://localhost:8100/build/vendor.js:5800:16 [716]@http://localhost:8100/build/main.js:10691:1 webpack_require@http://localhost:8100/build/vendor.js:55:12 webpackJsonpCallback@http://localhost:8100/build/vendor.js:26:23 @http://localhost:8100/build/main.js:1:1
Any idea?
Thanks a lot