1 files changed, 6 insertions, 1 deletions
diff --git a/src/main/java/org/shedlang/compiler/ShedCompiler.java b/src/main/java/org/shedlang/compiler/ShedCompiler.java
index 34cdad23..eb27588a 100644
--- a/src/main/java/org/shedlang/compiler/ShedCompiler.java
+++ b/src/main/java/org/shedlang/compiler/ShedCompiler.java
@@ -156,7 +156,12 @@ public class ShedCompiler {
             var namespaceNameParts = StreamSupport.stream(sourceRoot.relativize(sourceFilePath).spliterator(), false)
                 .map(element -> {
                     var string = element.toString();
-                    return string.substring(0, string.lastIndexOf('.'));
+                    var lastDotIndex = string.lastIndexOf('.');
+                    if (lastDotIndex == -1) {
+                        return string;
+                    } else {
+                        return string.substring(0, lastDotIndex);
+                    }
                 })
                 .toList();
             var namespaceName = new NamespaceName(namespaceNameParts);