Adds cargo and adds nix to editor config.

Some puzzles have solutions which are too large for `u32`s.

.cargo/config.toml

@@ -9,4 +9,4 @@ all = "run --quiet --release -- all"
 time = "run --quiet --release -- time"
 
 [env]
-AOC_YEAR = "2024"
+AOC_YEAR = "2025"

.editorconfig

@@ -15,3 +15,7 @@ trim_trailing_whitespace = false
 
 [*.md]
 trim_trailing_whitespace = false
+
+[*.nix]
+indent_size = 2
+

.envrc

@@ -0,0 +1 @@
+use flake

.gitignore

@@ -28,3 +28,6 @@ dhat-heap.json
 # Benchmarks
 
 data/timings.json
+
+# Direnv stuff
+.direnv/

Cargo.lock

@@ -1,6 +1,6 @@
 # This file is automatically @generated by Cargo.
 # It is not intended for manual editing.
-version = 3
+version = 4
 
 [[package]]
 name = "addr2line"
@@ -19,7 +19,7 @@ checksum = "f26201604c87b1e01bd3d98f8d5d9a8fcbb815e8cedb41ffccbeb4bf593a35fe"
 
 [[package]]
 name = "advent_of_code"
-version = "0.11.0"
+version = "0.12.0"
 dependencies = [
  "chrono",
  "dhat",

Cargo.toml

@@ -1,8 +1,8 @@
 [package]
 name = "advent_of_code"
-version = "0.11.0"
+version = "0.12.0"
 authors = ["Felix Spöttel <1682504+fspoettel@users.noreply.github.com>"]
-edition = "2021"
+edition = "2024"
 default-run = "advent_of_code"
 publish = false
 

README.md

@@ -282,14 +282,10 @@ You can pass the report a tool like [dh-view](https://nnethercote.github.io/dh_v
 -   [itertools](https://crates.io/crates/itertools): Extends iterators with extra methods and adaptors. Frequently useful for aoc puzzles.
 -   [regex](https://crates.io/crates/regex): Official regular expressions implementation for Rust.
 
-A curated list of popular crates can be found on [blessred.rs](https://blessed.rs/crates).
+A curated list of popular crates can be found on [blessed.rs](https://blessed.rs/crates).
 
 Do you have aoc-specific crate recommendations? [Share them!](https://github.com/fspoettel/advent-of-code-rust/edit/main/README.md)
 
-## Common pitfalls
-
--   **Integer overflows:** This template uses 32-bit integers by default because it is generally faster - for example when packed in large arrays or structs - than using 64-bit integers everywhere. For some problems, solutions for real input might exceed 32-bit integer space. While this is checked and panics in `debug` mode, integers [wrap](https://doc.rust-lang.org/book/ch03-02-data-types.html#integer-overflow) in `release` mode, leading to wrong output when running your solution.
-
 ## Footnotes
 
 [^1]: The session cookie might expire after a while (~1 month) which causes the downloads to fail. To fix this issue, refresh the `.adventofcode.session` file.

flake.lock

@@ -0,0 +1,61 @@
+{
+  "nodes": {
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1765311797,
+        "narHash": "sha256-mSD5Ob7a+T2RNjvPvOA1dkJHGVrNVl8ZOrAwBjKBDQo=",
+        "owner": "nixos",
+        "repo": "nixpkgs",
+        "rev": "09eb77e94fa25202af8f3e81ddc7353d9970ac1b",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nixos",
+        "ref": "nixos-25.11",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "nixpkgs": "nixpkgs",
+        "utils": "utils"
+      }
+    },
+    "systems": {
+      "locked": {
+        "lastModified": 1681028828,
+        "narHash": "sha256-Vy1rq5AaRuLzOxct8nz4T6wlgyUR7zLU309k9mBC768=",
+        "owner": "nix-systems",
+        "repo": "default",
+        "rev": "da67096a3b9bf56a91d16901293e51ba5b49a27e",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nix-systems",
+        "repo": "default",
+        "type": "github"
+      }
+    },
+    "utils": {
+      "inputs": {
+        "systems": "systems"
+      },
+      "locked": {
+        "lastModified": 1731533236,
+        "narHash": "sha256-l0KFg5HjrsfsO/JpG+r7fRrqm12kzFHyUHqHCVpMMbI=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "11707dc2f618dd54ca8739b309ec4fc024de578b",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}

flake.nix

@@ -0,0 +1,31 @@
+{
+  inputs = {
+    nixpkgs.url = "github:nixos/nixpkgs?ref=nixos-25.11";
+    utils.url = "github:numtide/flake-utils";
+  };
+
+  outputs =
+    {
+      self,
+      nixpkgs,
+      utils,
+    }:
+    utils.lib.eachDefaultSystem (
+      system:
+      let
+        pkgs = import nixpkgs { inherit system; };
+      in
+      {
+        devShell =
+          with pkgs;
+          mkShell {
+            buildInputs = [
+              rustc
+              cargo
+              clippy
+              rustfmt
+            ];
+          };
+      }
+    );
+}

src/main.rs

@@ -1,5 +1,5 @@
 use advent_of_code::template::commands::{all, download, read, scaffold, solve, time};
-use args::{parse, AppArguments};
+use args::{AppArguments, parse};
 
 #[cfg(feature = "today")]
 use advent_of_code::template::Day;

src/template.txt

@@ -1,10 +1,10 @@
 advent_of_code::solution!(%DAY_NUMBER%);
 
-pub fn part_one(input: &str) -> Option<u32> {
+pub fn part_one(input: &str) -> Option<u64> {
     None
 }
 
-pub fn part_two(input: &str) -> Option<u32> {
+pub fn part_two(input: &str) -> Option<u64> {
     None
 }
 

src/template/commands/download.rs

@@ -1,9 +1,11 @@
-use crate::template::{aoc_cli, Day};
+use crate::template::{Day, aoc_cli};
 use std::process;
 
 pub fn handle(day: Day) {
     if aoc_cli::check().is_err() {
-        eprintln!("command \"aoc\" not found or not callable. Try running \"cargo install aoc-cli\" to install it.");
+        eprintln!(
+            "command \"aoc\" not found or not callable. Try running \"cargo install aoc-cli\" to install it."
+        );
         process::exit(1);
     }
 

src/template/commands/read.rs

@@ -1,10 +1,12 @@
 use std::process;
 
-use crate::template::{aoc_cli, Day};
+use crate::template::{Day, aoc_cli};
 
 pub fn handle(day: Day) {
     if aoc_cli::check().is_err() {
-        eprintln!("command \"aoc\" not found or not callable. Try running \"cargo install aoc-cli\" to install it.");
+        eprintln!(
+            "command \"aoc\" not found or not callable. Try running \"cargo install aoc-cli\" to install it."
+        );
         process::exit(1);
     }
 

src/template/commands/time.rs

@@ -2,7 +2,7 @@ use std::collections::HashSet;
 
 use crate::template::run_multi::run_multi;
 use crate::template::timings::Timings;
-use crate::template::{all_days, readme_benchmarks, Day};
+use crate::template::{Day, all_days, readme_benchmarks};
 
 pub fn handle(day: Option<Day>, run_all: bool, store: bool) {
     let stored_timings = Timings::read_from_file();

src/template/day.rs

@@ -24,19 +24,13 @@ pub struct Day(u8);
 impl Day {
     /// Creates a [`Day`] from the provided value if it's in the valid range,
     /// returns [`None`] otherwise.
-    pub fn new(day: u8) -> Option<Self> {
+    pub const fn new(day: u8) -> Option<Self> {
         if day == 0 || day > 25 {
             return None;
         }
         Some(Self(day))
     }
 
-    // Not part of the public API
-    #[doc(hidden)]
-    pub const fn __new_unchecked(day: u8) -> Self {
-        Self(day)
-    }
-
     /// Converts the [`Day`] into an [`u8`].
     pub fn into_inner(self) -> u8 {
         self.0
@@ -137,24 +131,19 @@ impl Iterator for AllDays {
 /// Creates a [`Day`] value in a const context.
 #[macro_export]
 macro_rules! day {
-    ($day:expr) => {{
-        const _ASSERT: () = assert!(
-            $day != 0 && $day <= 25,
-            concat!(
-                "invalid day number `",
-                $day,
-                "`, expecting a value between 1 and 25"
-            ),
-        );
-        $crate::template::Day::__new_unchecked($day)
-    }};
+    ($day:expr) => {
+        const {
+            $crate::template::Day::new($day)
+                .expect("invalid day number, expecting a value between 1 and 25")
+        }
+    };
 }
 
 /* -------------------------------------------------------------------------- */
 
 #[cfg(feature = "test_lib")]
 mod tests {
-    use super::{all_days, Day};
+    use super::{Day, all_days};
 
     #[test]
     fn all_days_iterator() {

src/template/readme_benchmarks.rs

@@ -2,8 +2,8 @@
 /// The approach taken is similar to how `aoc-readme-stars` handles this.
 use std::{fs, io};
 
-use crate::template::timings::Timings;
 use crate::template::Day;
+use crate::template::timings::Timings;
 
 static MARKER: &str = "<!--- benchmarking table --->";
 
@@ -99,7 +99,7 @@ pub fn update(timings: Timings) -> Result<(), Error> {
 
 #[cfg(feature = "test_lib")]
 mod tests {
-    use super::{update_content, MARKER};
+    use super::{MARKER, update_content};
     use crate::{day, template::timings::Timing, template::timings::Timings};
 
     fn get_mock_timings() -> Timings {

src/template/run_multi.rs

@@ -1,6 +1,6 @@
 use std::{collections::HashSet, io};
 
-use crate::template::{Day, ANSI_BOLD, ANSI_ITALIC, ANSI_RESET};
+use crate::template::{ANSI_BOLD, ANSI_ITALIC, ANSI_RESET, Day};
 
 use super::{
     all_days,
@@ -67,7 +67,7 @@ pub fn get_path_for_bin(day: Day) -> String {
 /// All solutions live in isolated binaries.
 /// This module encapsulates interaction with these binaries, both invoking them as well as parsing the timing output.
 pub mod child_commands {
-    use super::{get_path_for_bin, Error};
+    use super::{Error, get_path_for_bin};
     use crate::template::Day;
     use std::{
         io::{BufRead, BufReader},
@@ -174,7 +174,7 @@ pub mod child_commands {
             .split(" samples)")
             .next()?
             .split('(')
-            .last()?
+            .next_back()?
             .split('@')
             .next()?
             .trim();

src/template/runner.rs

@@ -1,13 +1,13 @@
 /// Encapsulates code that interacts with solution functions.
 use std::fmt::Display;
 use std::hint::black_box;
-use std::io::{stdout, Write};
+use std::io::{Write, stdout};
 use std::process::Output;
 use std::time::{Duration, Instant};
 use std::{cmp, env, process};
 
 use crate::template::ANSI_BOLD;
-use crate::template::{aoc_cli, Day, ANSI_ITALIC, ANSI_RESET};
+use crate::template::{ANSI_ITALIC, ANSI_RESET, Day, aoc_cli};
 
 pub fn run_part<I: Copy, T: Display>(func: impl Fn(I) -> Option<T>, input: I, day: Day, part: u8) {
     let part_str = format!("Part {part}");
@@ -156,7 +156,9 @@ fn submit_result<T: Display>(
     }
 
     if aoc_cli::check().is_err() {
-        eprintln!("command \"aoc\" not found or not callable. Try running \"cargo install aoc-cli\" to install it.");
+        eprintln!(
+            "command \"aoc\" not found or not callable. Try running \"cargo install aoc-cli\" to install it."
+        );
         process::exit(1);
     }