JSII .NET System.Exception: Cannot use import statement outside a module

[hakenmt]

I've written a construct in Typescript, it tests, builds, and packages successfully. The only non CDK thing I'm importing is "path" to get the full path for a Lambda function. When I try to use the construct in a .NET project, I get the following exception:

Unhandled exception. System.Exception: Cannot use import statement outside a module
   at Amazon.JSII.Runtime.Services.Client.TryDeserialize[TResponse](String responseJson)
   at Amazon.JSII.Runtime.Services.Client.ReceiveResponse[TResponse]()
   at Amazon.JSII.Runtime.Services.Client.Send[TRequest,TResponse](TRequest requestObject)
   at Amazon.JSII.Runtime.Services.Client.Load(LoadRequest request)
   at Amazon.JSII.Runtime.Services.Client.Load(String name, String version, String tarball)
   at Amazon.JSII.Runtime.Services.Client.LoadPackage(String package, String version, String tarballPath)
   at Amazon.JSII.Runtime.Deputy.JsiiTypeAttributeBase.Load(Assembly assembly)
   at Amazon.JSII.Runtime.Deputy.JsiiTypeAttributeBase..ctor(Type nativeType, String fullyQualifiedName)
   at Amazon.JSII.Runtime.Deputy.JsiiClassAttribute..ctor(Type nativeType, String fullyQualifiedName, String parametersJson)
   at System.Reflection.CustomAttribute._CreateCaObject(RuntimeModule pModule, RuntimeType type, IRuntimeMethodInfo pCtor, Byte** ppBlob, Byte* pEndBlob, Int32* pcNamedArgs)
   at System.Reflection.CustomAttribute.CreateCaObject(RuntimeModule module, RuntimeType type, IRuntimeMethodInfo ctor, IntPtr& blob, IntPtr blobEnd, Int32& namedArgs)
   at System.Reflection.CustomAttribute.AddCustomAttributes(ListBuilder`1& attributes, RuntimeModule decoratedModule, Int32 decoratedMetadataToken, RuntimeType attributeFilterType, Boolean mustBeInheritable, ListBuilder`1 derivedAttributes)
   at System.Reflection.CustomAttribute.GetCustomAttributes(RuntimeType type, RuntimeType caType, Boolean inherit)
   at System.Attribute.GetCustomAttributes(MemberInfo element, Type attributeType, Boolean inherit)
   at System.Reflection.CustomAttributeExtensions.GetCustomAttribute[T](MemberInfo element)
   at Amazon.JSII.Runtime.Services.TypeCache.CacheTypes(Assembly assembly)
   at Amazon.JSII.Runtime.Services.TypeCache.Refresh()
   at Amazon.JSII.Runtime.Services.TypeCache.TryGetType[T](String fullyQualifiedName)
   at Amazon.JSII.Runtime.Services.TypeCache.TryGetClassType(String fullyQualifiedName)
   at Amazon.JSII.Runtime.Services.Converters.ValueConverter.<TryConvertCustomType>g__IsReferenceType|17_0(<>c__DisplayClass17_0&)
   at Amazon.JSII.Runtime.Services.Converters.ValueConverter.TryConvertCustomType(Type type, IReferenceMap referenceMap, Object value, Boolean isOptional, String fullyQualifiedName, Object& result)
   at Amazon.JSII.Runtime.Services.Converters.ValueConverter.TryConvert(IOptionalValue optionalValue, Type type, IReferenceMap referenceMap, Object value, Object& result)
   at Amazon.JSII.Runtime.Services.Converters.FrameworkToJsiiConverter.TryConvert(IOptionalValue optionalValue, IReferenceMap referenceMap, Object value, Object& result)
   at Amazon.JSII.Runtime.Deputy.DeputyBase.<>c__DisplayClass20_0.<ConvertArguments>b__0(Parameter parameter, Object frameworkArgument)
   at System.Linq.Enumerable.ZipIterator[TFirst,TSecond,TResult](IEnumerable`1 first, IEnumerable`1 second, Func`3 resultSelector)+MoveNext()
   at System.Collections.Generic.LargeArrayBuilder`1.AddRange(IEnumerable`1 items)
   at System.Collections.Generic.EnumerableHelpers.ToArray[T](IEnumerable`1 source)
   at Amazon.JSII.Runtime.Deputy.DeputyBase.ConvertArguments(Parameter[] parameters, Object[] arguments)
   at Amazon.JSII.Runtime.Deputy.DeputyBase..ctor(DeputyProps props)
   at Constructs.Construct..ctor(DeputyProps props)
   at Amazon.CDK.Stack..ctor(Construct scope, String id, IStackProps props)
   at MultiAzWorkshop.MultiAZWorkshopStack..ctor(App scope, String id, StackProps props) in /Users/mhaken/source/multi-az-workshop/cdk/MultiAZWorkshopStack.cs:line 53
   at MultiAzWorkshop.Program.Main(String[] args) in /Users/mhaken/source/multi-az-workshop/cdk/Program.cs:line 18

I'm unsure if this is a bug, or if this has something to do with the configuration of my typescript project?

[hakenmt]

Going to answer my own question in case this comes up in a search. I was exporting a bunch of classes and interfaces in my "main" file. In a few other .ts files i was importing from this main file, effectively making a circular import/export. Importing directly from the appropriate file containing the class fixed the problem.

[github-actions[bot]]

Hello! Reopening this discussion to make it searchable.