aoc-template

This is an (opinionated) Advent of Code template for solutions in Haskell.

To use:

• Clone this repository
• Set up a new branch for the year's solutions
• Change the package name, update the GitHub link, etc. You'll also want to remove the .cabal file and let stack generate a new one.
• Fill in the solutions and have fun!

When running from the command line you can pass the option -d/--day DAY to run a specific day's solutions. If you do this, then you can also pass -i/--input FILE to specify an input file; by default, the program will look for it in input/DayXX.txt. You can also pass the argument --all-days and all days will be run in order, assuming the input files are in their default places.

Example usage:

• stack run -- -d 9: Runs Day 9's solutions.
• stack run -- --day 14 --input "wibble.txt": Runs Day 14's solutions, using the input file "wibble.txt".
• stack run -- --all-days: Runs the solutions from all days.

If you think the structure of the Day files needs changing to better suit your needs (before starting the project), then make the appropriate changes in src/Days/Day01.hs and run the apply_changes.zsh file. This will copy Day01 to all the other days, changing Day01 for DayXX as appropriate.

Default Language Extensions

I've turned several language extensions on by default. These are:

• DeriveFoldable
• DeriveFunctor
• EmptyCase
• FlexibleContexts
• FlexibleInstances
• GADTs
• InstanceSigs
• LambdaCase
• MultiParamTypeClasses
• MultiWayIf
• NumericUnderscores
• OverloadedStrings
• RecordWildCards
• TupleSections
• ScopedTypeVariables

The reason for these should be pretty clear in most cases.

Default Dependencies

The default package dependencies for this project are:

• directory: This is just for checking if the provided input file exists.
• containers: For Map, Set, and so on.
• text: Because Strings are bad.
• attoparsec: For the input parser for each day.
• optparse-applicative: For command line parsing.
• mtl: Mainly in anticipation that State might be useful. ExceptT is also used to catch exceptions in runDay.
• vector: In anticipation that fixed-length arrays will come in handy.
• pointedlist: Because Advent of Code loves circular lists