Assignment 4: Executables, File I/O, S-expressions

In this assignment, you will write an executable to count the number of occurances of each OCaml keyword in a given directory.

File structure and requirements

  • Use this zip file as the starting point for your assignment.
  • You are given instructions in src/lib/histogram.mli to write a Histogram module that you will use to count keywords.
    • Implement this module in src/lib/histogram.ml.
    • The starter code is incomplete as given. You will need to read the mli file and fill in some well-typed value in the ml file for each declaration to get the project to build.
    • You may add to the mli if needed, but you may not change or delete anything that exists there as given.
    • The histogram works on keywords. A Keyword module is implemented for you in src/lib/keyword.ml.
  • You’ll write an executable in bin/keywordcount.ml. There are full instructions in that file, and there are lots of tips for this assignment. Some starter code is provided to help with command-line argument parsing.
    • Before beginning anything on this assignment, you should read src/bin/keywordcount.ml.
  • If you need any helper functions that might be tested, then they go in src/lib/utils.ml(i).
  • You are given some initial (incomplete) tests in src-test/hist_tests.ml and src-test/exec_tests.ml.
    • You must add at least 10 non-redundant assert_equal statements to src-test/tests.ml to test your code in the Histogram and/or Utils modules.
    • You are not graded on the total testing coverage of any part of your code, but moving helper functions to src/lib/utils.ml(i) gives you more ways to hit those 10 non-redundant assert_equal statements.
  • We have given you dune files which generally should work, but you can add libraries if needed.

Submission and Grading

  • Follow the same protocol for Gradescope submission as previous assignments.
    • do a final dune clean; dune build from the main directory and submit the _build/default/assignment4.zip file.
  • The submitted files include only the files you are supposed to edit, along with your dune files and any additional testing resources in the test/ directory. You do not submit the provided ml test files, but you will submit the mli files.
  • We will grade the style of your code. Please consult the FPSE Style Guide.
  • You will also be graded on your added tests.