CPSC 421-020 Object-Oriented Programming Spring 2026

Week 4 Class 7 Thu Feb 05 Posted: Feb 05

After Class

• Project 1 Part v1b graded. Feedback as issues in GitHub (look for the label v1a), and scores out of 20 in Brightspace.

Announcements

• Project 1 Posted due dates for parts v1c to v1e
• Project 1 Your repository has a pull request for xml_parser to use for part v1d. After you accept the pull request on GitHub, you have to git pull it into your local repository (even in a codespace).
• Guide: srcML Guide to using srcML. I will add some more instruction to this.

• GitHub Codespaces I updated the image, srcml/codespaces, used by our projects in the codespace container. Besides new versions of the installed packages, including cmake, you can now use the manual utility, man g++, and even man srcml.

  When an image is updated, existing codespaces are still using the old image. To use the new image, you must start a new up a new codespace. You also probably want to delete the old one so you don't get confused. Make sure you committed and pushed in the codespace

• Exercise 22: For Semantics II due by 3:30 pm on Fri Feb 6

• Exercise 21: Include Guard Name Quiz Available after class from a link in Brightspace.

  You may want to review your notes on include guard names before taking it. Answers must be exact.

Agenda

• Exercise 23: Role of Include Files

  For each of the following, write the code necessary to call the function. Include all error handling:

  • Combine.cpp uses Move.hpp
  • ReadFile.cpp uses ReadLine.hpp

  An include file is not for the developer of the corresponding .cpp file. It is so that the developer calling the function can use it, and use it properly. It has to be sufficient for the developer to call the function, but not include anything more.

  Facts

  • The number of developers and times a function is called is much higher than the number of developers who write (or modify) a function.
  • Most users of a function will not have access to the implementation file.
  • Even if a user of a function has access to the implementation file, they do not want to read it to figure out how to call a function.

  The results of part v1b is that overall there is a misunderstanding of the purpose of an include file.

  From the function caller's perspective:

  • Clear, single include file to use the feature. The include files is self-sufficient and I can include it wherever I need it in whatever order I want.
  • The include file has no extra dependencies (e.g., include files that are not needed).
  • The include file has a function declaration which gives me the name, parameters, and return type.
  • The include file has comments and naming that tells me what the parameters are for.
  • The include file has comments describing the general purpose.
  • The include file has comments given specific return values (or OUT values) and what they mean.
  • The caller of a function does not want access to the function definition.
  • They will most likely use the function from a library, which does not contain the original source code.
  • They don't care about the original source code.

  From the function developer's perspective:

  • They provide the include file so that others (and themselves) can easily call the function.
  • The better they meet the needs of the callers of the function, the more people will use the function.
  • The more people that use it, the less of a problem they will be to the developer of the function if the include file is good.
• Guide: Coding Standard
• Exercise 24: Coding Standard Crossword
• Notes: Free Function Stereotypes
• Exercise 25: Free Function Stereotypes Crossword
• Notes: Concerns

• Exercise 20: Rainfall V Continuing on using the workflow from Rainfall I. As before, you can follow along and see the commits that I make in class:

  OOPS26-Rainfall-020

Unless otherwise noted, exercises are due by 3:30 pm on Monday, Feb 9