Gladvent

An Advent Of Code runner for Gleam

This library is intended to be imported to your gleam project and used as a command runner for your advent of code project in gleam.

To add this library to your project run: gleam add gladvent and add import gladvent to your main gleam file.

Using the library

This library provides 2 options to run your advent of code solvers, once you’ve added gladvent as a dependency via gleam add gladvent:

1. The easiest way: call it via gleam run -m gladvent [ARGS], not requiring a custom main() function.
2. The easy way: simply add gladvent.main() to the end of your project’s main function.

Multi-year support

Gladvent now comes with out-of-the-box multi-year support via the --year flag when running it.

For convenience it defaults to the current year. Therefore, passing --year=YEAR to either the run, run all or new commands will use the year specified or the current year if the flag was not provided.

Available commands

This project provides your application with 2 commands, new and run:

• new: create src/days/*.gleam and input/*.txt files that correspond to the specified days

• format: gleam run -m gladvent new a b c ...

• used like gleam run -m gladvent new 1 2 with days 1 and 2 creates input/day_1.txt and input/day_2.txt as well as src/days/day_1.gleam and src/days/day_2.gleam

• run: run the specified days

• format: gleam run -m gladvent run a b c ...

• flags:

  • --timeout: gleam run -m gladvent run --timeout={timeout in ms} a b c ...
    • usage example: gleam run run --timeout=1000 1 2 with timeout 1000 milliseconds and days 1 and 2, runs and prints the output of running the run function of day_1.gleam and day_2.gleam
  • --allow-crash: runs days without the use of rescue functionality, rendering output text more verbose but also allowing for stacktraces to be printed
    • usage example: gleam run -m gladvent run 1 2 3 --allow-crash

• run all: run all registered days

• format: gleam run -m gladvent run all

• flags:

  • --timeout: gleam run -m gladvent run all --timeout={timeout in ms}
    • usage example: gleam run run --timeout=1000 1 2 with timeout 1000 milliseconds and days 1 and 2, runs and prints the output of running the run function of day_1.gleam and day_2.gleam
  • --allow-crash: runs days without the use of rescue functionality, rendering output text more verbose but also allowing for stacktraces to be printed
    • usage example: gleam run -m gladvent run all --allow-crash

Note:

• the new command creates source files in src/aoc_<YEAR>/ and input files in the input/<YEAR> directory.
• the run command expects input files to be in the input/<YEAR> directory, and code to be in src/aoc_<YEAR>/
• any triggered assert will be captured and printed, for example: error: assert - Assertion pattern match failed in module days/day_1 in function pt_1 at line 2 with value 2
• any message in a todo will be captured and printed, for example: error: todo - test in module days/day_1 in function pt_2 at line 7

Seeing help messages

• To see available subcommands: gleam run -m gladvent -- --help
• To see help for the run command: gleam run -m gladvent run --help
• To see help for the run command: gleam run -m gladvent run all --help
• To see help for the new command: gleam run -m gladvent new --help

General Workflow

Where X is the day you’d like to add (when using gladvent.main()):

Note: this method requires all day solutions be in src/days/ with filenames day_X.gleam, each solution module containing fn pt_1(String) -> Int and a fn pt_2(String) -> Int

1. run gleam run -m gladvent run new X
2. add your input to input/<YEAR>/day_X.txt
3. add your code to src/aoc_<YEAR>/day_X.gleam
4. run gleam run -m gladvent run X

Reusable parse funtions

As of v0.7.0 gladvent supports modules with functions that provide a pub fn parse(String)->a where the type a matches with the type of the argument for the runner functions pt_1 and pt_2. If this function is present, gladvent will pick it up and run it only once, providing the output to both runner functions.

An example of which looks like this:

pub fn parse(input: String) -> Int {
   let assert Ok(i) = int.parse(input)
   i
}

pub fn pt_1(input: Int) -> Int {
   i + 1
}

pub fn pt_2(input: Int) -> Int {
   i + 2
}

Note: gladvent now leverages gleam’s export package-interface functionality to type-check your parse and pt_{1|2} functions to make sure that they are compatible with each other.

FAQ

Why did you make this?

It seemed fun, I like small command line utilities and I wanted a way to get advent of code done in gleam without having the additional overhead of lots of copy-pasting and connecting things to get it to run

Why does this not download the input from the advent of code website?

A few reasons:

1. I wanted to keep this utility as simple as possible to start with
2. I like the advent of code website and I felt like it was a shame to circumvent visiting it, especially since you should access it to read the daily challenge. On top of that, I would like to avoid spamming the advent of code api if possible.

Why run as a command line utility and not just use unit tests?

I thought a lot about that and I prefer the overall interactivity of a CLI better, as well as allowing for endless runs or runs with configurable timeouts. Having it run as part of eunit doesnt provide as much flexibility as I would like.