# Modula-2 diagnostics — step 1

This first diagnostics layer is deliberately lightweight. It does **not** replace
Coco/R. It provides immediate editor feedback for a small set of structural
errors while the real parser/LSP is being prepared.

It currently checks:

- unterminated `(* ... *)` comments;
- unterminated string literals;
- presence of the module header;
- `;` after the module header;
- presence of the final `END <ModuleName>.`;
- module-name consistency between the header and final `END`;
- the final period after `END <ModuleName>`.

The diagnostics are published through the VS Code-compatible
`DiagnosticCollection`, which Theia displays directly in the editor.

The next stage will replace the structural checks with diagnostics generated by
the Coco/R parser, while keeping the same editor diagnostic mechanism.