ConnorBaker

2024-03-28 Explaining Dependency Offsets And Splicing

Most of this is summarized from https://github.com/NixOS/nixpkgs/blob/bc061915ac2cf395e4d1f021cb565f495edfa24a/doc/stdenv/cross-compilation.chapter.md.

Dependency Offsets

In Nixpkgs, dependency offsets are the relative positioning of dependencies in the build process with respect to the build, host, and target platforms. In the case we're not doing cross-compilation, the build, host, and target platforms are the same, and none of this really matters. (Although, with strictDeps = true it can be important as you're telling Nix to enforce separation between build-time and run-time dependencies.)

Some key points:

ConnorBaker

function human_readable(size) {
  split("B KB MB GB TB PB", units); # Include PB in the units array to avoid separate handling
  unit_idx = 1; # Start with bytes

  while (size >= 1024 && unit_idx < length(units)) {
      size /= 1024;
      unit_idx++;
  }

  return sprintf("%.6f %s", size, units[unit_idx]);

ConnorBaker

Important

This review was run against commit ########.

Note

Template nixpkgs-review command:

PR="301416" \

ConnorBaker

#!/usr/bin/env bash

set -euo pipefail

json_cuda_packages_categorized=$(nix eval --impure --json .#cudaPackages --apply '
  attrs:
  let
    drvKind = drvName:
      let
        drv = attrs.${drvName};

ConnorBaker

# Clone repositories
FROM docker.io/bitnami/git:2.39.0@sha256:8802a1053f0a75c948da43c0d04e591b500381447745f0b5f75d3cf85509626c as git_base

# Basic git configuration
RUN git config --global advice.detachedHead false \
    && git config --global init.defaultBranch main

# Install xz-utils for decompressing tarballs
RUN --mount=type=cache,target=/var/cache/apt \
    export DEBIAN_FRONTEND=noninteractive \

ConnorBaker

{-# LANGUAGE TemplateHaskell #-}

module Tasty.Runners.Buildkite.History where

import Tasty.Runners.Buildkite.Span ( Span )

import Data.Aeson (defaultOptions, camelTo2)
import Data.Aeson.TH (deriveJSON, Options (fieldLabelModifier))

data History = History {

ConnorBaker

connorbaker@Connors-MacBook-Pro nixpkgs % nix run nixpkgs#nixpkgs-review rev HEAD    
$ git -c fetch.prune=false fetch --no-tags --force https://github.com/NixOS/nixpkgs master:refs/nixpkgs-review/0
From https://github.com/NixOS/nixpkgs
   1730f14d79a..1a763b8465a  master     -> refs/nixpkgs-review/0
$ git worktree add /Users/connorbaker/.cache/nixpkgs-review/rev-2cc754a7baa72659430ec961608f0fc1dbe128df/nixpkgs 1a763b8465ad9aca80869792d8a5abac2c4f6373
Preparing worktree (detached HEAD 1a763b8465a)
Updating files: 100% (30225/30225), done.
HEAD is now at 1a763b8465a Merge pull request #168049 from NixOS/haskell-updates
$ nix-env --option system aarch64-darwin -f /Users/connorbaker/.cache/nixpkgs-review/rev-2cc754a7baa72659430ec961608f0fc1dbe128df/nixpkgs -qaP --xml --out-path --show-trace
$ git merge --no-commit --no-ff 2cc754a7baa72659430ec961608f0fc1dbe128df

ConnorBaker

these 150 paths will be fetched (104.70 MiB download, 655.11 MiB unpacked):
  /nix/store/0ak4ybyr97gda5idyfgx4aj9anpja3hr-aws-c-auth-0.6.8
  /nix/store/0f7kd5smkxkq0b36qgwiqsng795353fi-perl5.34.0-Test-Needs-0.002006
  /nix/store/0hl87pfmhp0q1jbk0dmf8kasvi3ya8ps-apple-framework-QuartzCore-11.0.0
  /nix/store/0mr7pcp32apiipy2chwbm40xiyr4rwk2-bash-interactive-5.1-p12-man
  /nix/store/0sk7avb5ssjkgmlxy5f3nblh4q482b9v-perl5.34.0-HTML-Tagset-3.20
  /nix/store/0yg297zlk50wjr65dqkw74ym1h69cjgb-apple-framework-NetFS-11.0.0
  /nix/store/10nzv9njvi32rai2mw5wp15dva05f5q6-perl5.34.0-CGI-4.51
  /nix/store/1661xd8g1bc9sw5cvy7da4fp6b51qkpn-nix-2.5.1-man
  /nix/store/1nj00g8034rp8h58as2bb0jqlxf6vp44-gettext-0.21

ConnorBaker

rg "(withPackages *=)|(withPlugins *=)" --ignore-case --glob '*.nix'

ConnorBaker

fst = (a) -> (b) -> a
snd = (a) -> (b) -> b
_Pair2 = (a) -> (b) -> (p2) -> p2(a)(b)
show_pair = (p2) -> p2((a) -> (b) -> "(${a}, ${b})")
test_p2 = _Pair2('A')('B')

// (A, B)
println(show_pair(test_p2))
// A
println(test_p2(fst))