Language and Library Features for Teaching

I’ve written several posts in the past couple of years about the minimal set of features I need in a language in order to write books like Software Design by Example and its upcoming translation into Python. As the latter nears completion, I thought it might be helpful to itemize the libraries I need as well; if you’re building the standard library for a new language, these might be a good place to start. In order of priority, books like these need:

• system utilities (command-line arguments, environment variables, etc.)
• date/time handling
• fixtures and mock objects for testing
• globbing
• file and path manipulation
• HTML parser (e.g., BeautifulSoup)
• CSV, JSON, and YAML (in that order)
• hashing (e.g., SHA-256)
• basic math functions
• introspection (e.g., Python’s inspect and ast modules)
• HTTP request handling
• string I/O
• packing and unpacking binary data
• a minimal HTTP server
• terminal window control (e.g., curses)
• dataframes (for analyzing performance data)
• pretty-printing data structures
• a plotting library (I realize this is probably too big for the standard library)