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Unguided callback
The aim of this callback is to develop your independence and project-planning skills and to prepare you for the unguided lab. In this callback, you will:
- Think of a modification or improvement you’d like to make to a previous lab.
- Write a specification describing the planned change:
- 2 or 3 sentences explaining what feature you plan to implement.
- 1 sentence explaining which course concepts you plan to use or illustrate.
- 1 sentence explaining the distribution of tasks among team members (all team members are expected to contribute equal effort to the final result).
- Implement the change.
- Receive a “checkoff” from a staff member:
- Give a short live demo of your feature.
- Walk the staff member through the code and tests that you wrote or modified, by showing them your Git history.
- Answer a few clarification questions.
Before you start, make sure to read the unguided callback policies in full for details on rules, submission, and grading.
Callback suggestions
Below are some suggestions for inspiration, but we hope most of you will come up with your own ideas! In all cases, make sure that you create adequate tests in addition to implementing the functionality.
Find
FFP3 (any team size)
Extend find with new kinds of filters (this will require modifying the supporting library to expose other properties of files and directories, the command-line interface to expose new flags, and the testing code to mock that data). Think carefully about how to test your new filters!
Baby’s first sentence (2-3 people)
Generalize the interface of find by allowing combinations of filters, such as -name foo -and -size +200c, -name foo -or -size +200c, or -not -name foo. Do you need a parser to support arbitrary combinations of filters? Or have we already seen an easier way to represent and evaluate complex expressions? (hint).
Boids
Loopy times (any team size)
Explore unguided geometries in the boid world: wrap the world on a torus, add wormholes to transport boids across the board, use non-euclidian distances to compute forces, etc.
Not all the same (any team size)
Invent multiple new boids classes and vary their speeds, colors, and behaviors: perhaps some boids escape certain forces; perhaps some boids have more influence on others; perhaps some boids chase other boids; etc.
Flocking in the rain (two people)
Merge neighboring boids when they get too close to each other, producing fewer, larger boids; adjust the rules of the world so that larger boids affect the world differently from smaller ones.
Squaring the circle (2 people)
Rewrite boids to use a fast datastructure to find neighbors. Good candidate datastructures are “spatial hashes” (very easy to implement yourself), “quad-trees”, or “bounded volume hierarchies”.
Calculator
Show your work (two people)
Implement a step-by-step interpreter for computation, showing reductions (substitutions) one by one (e.g. interpreting 2 * ((4 + 4) - 3) should print 2 * (8 - 3), then 2 * 5, and finally 10). Can you make this process more efficient?
Can it cook rice? (any team size)
Add a separate type of logical (boolean) expressions to the calculator, with operators like and, or, not, etc. Add a conditional construct (if) to the main type of expressions, using your new type of logical expressions for the condition in the if. (Suitable for 2 people. With more, add additional constructs beyond if, like while or do … while.)
Anagrams
Not wet (2 people)
Change the sentence-anagrams enumeration algorithm to produce results unique up to word permutations (that is, different sentences in the output cannot have the same words in different orders). Your algorithm should eliminate permutations as it computes anagrams (and not eliminate them after the fact). Measure the efficiency of the result using a benchmarking tool such as jmh.
Scalashop
Rose-tinted glasses (any team size)
Add one new image filter per team member.