Use new impl function, pass through set rather than slice

pkg/composableschemadsl/compiler/importer.go

@@ -34,13 +34,13 @@ func ImportFile(importContext *ImportContext) (*CompiledSchema, error) {
 	// TODO: do we want this sort of logging here?
 	log.Trace().Str("schema", string(schemaBytes)).Str("file", filePath).Msg("read schema from file")
 
-	compiled, err := Compile(InputSchema{
+	compiled, err := compileImpl(InputSchema{
 		// TODO: should this point to the schema file? What is this for?
 		Source:       input.Source("schema"),
 		SchemaString: string(schemaBytes),
 	},
+		importContext.names,
 		AllowUnprefixedObjectType(),
-		ExistingNames(importContext.names.AsSlice()),
 		SourceFolder(newSourceFolder),
 	)
 	if err != nil {