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Python Fundamentals / Lesson 12

Capstone: Task Tracker CLI

Build a command-driven task tracker that parses lines like `add`, `done`, and `list` — combining lists of dicts, string parsing, conditionals, and per-command functions.

python·~35 minutes·Lesson 12 of 12
Represent state as a list of dictionariesDispatch commands with conditionals and per-command functionsParse command lines with str.split(maxsplit=...)Print aligned, formatted output with f-strings
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Every command-line tool follows the same shape: parse a command, change some state, print the result. You'll build a small task tracker that does exactly that — reading commands from stdin and printing the current list on demand.

What you'll build

A program that reads commands (one per line) from stdin and handles three of them:

  • add <text> — append a task with the next id, marked not-done
  • done <id> — mark the task with that id as done
  • list — print every task, plus a "Done: x/y" summary line

Input (paste into the stdin tab)

add Buy groceries
add Finish report
add Call dentist
done 2
list

Expected output

1. [ ] Buy groceries
2. [x] Finish report
3. [ ] Call dentist
Done: 1/3
  • [ ] means not done, [x] means done.
  • The final Done: 1/3 shows completed / total.

Requirements

  • Store tasks as a list of dicts, each with id, text, and done.
  • Write one function per command: add_task(tasks, text), done_task(tasks, task_id), list_tasks(tasks).
  • add_task assigns the next id (1, 2, 3, …) and appends to the list.
  • Parse each line with line.split(maxsplit=1) so the task text can contain spaces.
  • Dispatch via if/elif: if cmd == "add": ... elif cmd == "done": ....

Hints

  • Read all input at once: sys.stdin.read().strip().splitlines().
  • line.split(maxsplit=1) gives ["add", "Buy groceries"] — the command, then the rest.
  • Inside done_task, loop to find the task whose id matches the given id, then set done = True.
  • In list_tasks, use mark = "x" if t["done"] else " " to pick the check mark.
  • Count completed with sum(1 for t in tasks if t["done"]).
  • Build it one command at a time — get add + list working first, then add done.