-### Technical issues
-- [-] testing framework
- - [x] run arbitrary code snippets
- - [x] check non-failures
- - [x] check expected output
- - [-] check expected exceptions
- - [x] semant stage
- - [ ] generalized expect `Output ('a option) | Exception of (exn -> bool)`
- - [x] run all book test case files
- - [-] grid view (cols: lex, pars, semant, etc.; rows: test cases.)
- - [x] implementation
- - [ ] refactoring
-- [ ] Travis CI
+![screenshot-tests-semant-done-head](screenshots/tests-semant-done-head.jpg)
+...
+![screenshot-tests-semant-done-tail](screenshots/tests-semant-done-tail.jpg)