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Features | How does it work? | Getting started | Examples | Similar

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NOTE: only supported on Linux, FreeBSD, and macOS due to the use of built-in plugin package.

Run your Go Advent of Code solutions with a single command. Write your solution and Elver will take care of the rest.

Features

• Automatically downloads and caches the input
• Runs your latest solution and times it
• Automatic benchmarking of your solution
• 0 third party dependencies

How does it work?

Elver uses plugin build mode to dynamically look up the solutions. These must reside in an Advent of Code folder under the main package.

Getting started

1. Install

$ go get github.com/aod/elver

2. Session token

Your https://adventofcode.com session token is required for downloading and caching the inputs.

2.A Environment variable

Set your Advent of Code session token in the environment variable AOC_SESSION.

2.B Config file

Alternatively you can store it in the aoc_session file in the following directory:

• Linux: $HOME/.config/elver/
• MacOS: /Library/Application Support/elver/
• Windows: %AppData%\elver\

3. Project structure

A solution for a day in an Advent of Code year is represented by 2 solvers for part A and B. All solvers are functions which satisfy the same signature where interface{} is the output:

func (input string) (interface{}, error)

For the plugin build mode to work correctly all solvers must be exported. The name of a solver is also very important for elver to work properly. It's name must satisfy the following set of rules:

• Starts with Day
• Followed by a valid Advent of Code day
  • Within (inclusive) range of 1..25
• Ends with A for part 1 or B for part 2.

Solvers are workspaced by the Advent of Code year which is also used as the folder name.

Example

// /2015/01.go
package main

import "errors"

func Day1A(input string) (interface{}, error) {
    return 42, nil
}

func Day1B(input string) (interface{}, error) {
    return nil, errors.New("Not implemented")
}

Running Elver in the root directory will output something like the following:

$ elver
AOC 2015
Day 1 A (312ns):
42
Day 1 B (956ns):
[ERROR] Not implemented

Benchmarking

Run Elver with the -b flag to benchmark your latest solution:

$ elver -b
AOC 2015
Day 1 A (N=231919370, 5 ns/op, 0 bytes/op, 0 allocs/op):
42
Day 1 B (N=0, 0 ns/op, 0 bytes/op, 0 allocs/op):
[ERROR] Not implemented

Examples

Running the latest solvers:

$ elver

Running the latest solvers of a specific year:

$ elver -y 2017

Running the latest solvers of a specific day:

$ elver -d 21

Running the specific solvers of a year and day:

$ elver -y 2017 -d 21

Benchmarking the solvers by adding the -b flag

$ elver -b
// Works with any combination of the previously mentioned flags e.g.:
$ elver -y 2017 -d 21 -b

Similar

These type of utility tools for Advent of Code also exist for other programming languages like cargo-aoc (Rust) and aocd (Python). Elver finds inspiration in these awesome projects so be sure to check them out as well!