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 --dev
:
- The easiest way: call it via
gleam run -m gladvent [ARGS]
, not requiring a custommain()
function. - The easy way: simply add
gladvent.main()
to the end of your project’smain
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.
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
- run
gleam run -m gladvent run new X
- add your input to
input/<YEAR>/day_X.txt
- add your code to
src/aoc_<YEAR>/day_X.gleam
- run
gleam run -m gladvent run X
Available commands
This project provides your application with 2 command groups, new
and run
:
New
new
: createsrc/aoc_<year>/day_<day>.gleam
andinput/<year>/<day>.txt
files that correspond to the specified days- format:
gleam run -m gladvent new a b c ...
- format:
Run
The run
command expects input files to be in the input/<year>
directory, and code to be in src/aoc_<year>/
(corresponding to the files created by the new
command).
-
run
: run the specified days- format:
gleam run -m gladvent run a b c ...
- format:
-
run all
: run all registered days- format:
gleam run -m gladvent run all
- format:
Note:
- any triggered
assert
,panic
ortodo
will be captured and printed, for example:
Part 1: error: todo - unimplemented in module aoc_2024/day_1 in function pt_1 at line 2
Reusable parse funtions
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 parse
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.
Defining expectations for easy refactoring
One of the most satisfying aspects of advent of code (for me), second only to that sweet feeling of first solving a problem, is iteration and refactoring.
Gladvent makes it easy for you to define expected outputs in your gleam.toml
for all your solutions so that you can have the confidence to refactor your solutions as much as you want without having to constantly compare with your submissions on the advent of code website..
Expectations in gleam.toml
Defining expectations is as simple as adding sections to your gleam.toml
in the following format:
[gladvent.<year as int>.<day as int>]
pt_1 = <int or string>
pt_2 = <int or string>
For example, to set the expectations for Dec 1st 2024 (2024 day 1) you would add something like:
[gladvent.2024.1]
pt_1 = 1
pt_2 = 2
When running, gladvent will detect whether a specific day has it’s expectations set and if so will print out the result for you.
Let’s say that your computed solution for 2024 day 1 is actually 1 for pt_1 and 3 for pt_2, the output will look like this:
Ran 2024 day 1:
Part 1: ✅ met expected value: 1
Part 2: ❌ unmet expectation: got 3, expected 2
Example inputs
Sometimes it’s helpful to run advent of code solutions against example inputs to verify expectations.
Gladvent now provides a --example
flag in both the new
and run
commands to conveniently support that workflow without needing to modify your actual problem input files.
Example input files will be generated at and run from input/<year>/<day>.example.txt
.
Note: gladvent will not compare your solution output against the expectations defined in gleam.toml
when running in example mode.
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:
- I wanted to keep this utility as simple as possible to start with
- 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 just 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. Other testing frameworks have been popping up but I leave the decision to use them up to you!