steshaw

package fpmax

import scala.util.Try
import scala.io.StdIn.readLine

object App0 {
  def main: Unit = {
    println("What is your name?")

    val name = readLine()

steshaw

Cached and Persistent Nix shell with direnv integration

Problem being solved

• the default direnv Nix integration from projects loads a Nix shell every new terminal or every time shell.nix and/or default.nix changes. On larger projects with a lot of Nix shell dependencies, that can cause the terminal to take more than 6 seconds to load, which significantly degrades the developer experience (DX).
• when a developer garbage collects in their Nix store, often the Nix shell dependencies are deleted also which causes a slow start the next time the project’s Nix shell is requested, also degrading developer experience (DX).

Solution outline

• on first Nix shell load, the Nix shell is evaluated fully such that direnv dumps the environment from the spawn Nix shell process

steshaw

#!/usr/bin/env bash

set -euo pipefail

#
# Some nixpkgs query scripts inspired by #nixos chat.
# Goal: find the HASH that will let an install command like:
#   nix-env -i -f https://github.com/NixOS/nixpkgs/archive/HASH.tar.gz -A hledger hledger-web hledger-ui
# install the latest available build of the packages, on all platforms of interest.
# These scripts don't seem to quite do that but they help.

steshaw

# Usage:
#
#   Find version:
#
#     $ nix-instantiate --eval --expr '(import ./pkg-versions.nix {}).pandoc'
#     { "1.13.1" = <CODE>; "1.16.0.2" = <CODE>; "1.17.1" = <CODE>; "1.19.2.1" = <CODE>; "1.19.2.4" = <CODE>; "2.0.6" = <CODE>; "2.2.1" = <CODE>; "2.7.1" = <CODE>; }
#     $ nix eval '(builtins.attrNames (import ./pkg-versions.nix {}).pandoc)'
#     [ "1.13.1" "1.16.0.2" "1.17.1" "1.19.2.1" "1.19.2.4" "2.0.6" "2.2.1" "2.7.1" ]
#     $ nix-instantiate --eval --expr 'builtins.attrNames (import ./pkg-versions.nix {}).pandoc'
#     [ "1.13.1" "1.16.0.2" "1.17.1" "1.19.2.1" "1.19.2.4" "2.0.6" "2.2.1" "2.7.1" ]

steshaw

module Main where

import Lib
import GHC as G
import GhcMake as G
import DynFlags
import SrcLoc as G
import GHC.Paths

import Control.Monad

steshaw

object test {
  import scalaz.zio._

  type UserID = String
  case class UserProfile(name: String)

  // The database module:
  trait Database {
    val database: Database.Service
  }

steshaw

/*.js

steshaw

object ScalaJSExample extends js.JSApp{
  def main() = {
    val xs = Seq(1, 2, 3)
    println(xs.toString)
    val ys = Seq(4, 5, 6)
    println(ys.toString)
    val zs = for{
      x <- xs
      y <- ys
    } yield x * y

steshaw

class Hash
  def safe_invert
    lazy
      .map {|a, b| [b, a]}
      .group_by {|a| a[0]}
      .map {|a, b| [a, b.collect {|c| c[1]}]}
      .to_h
  end
end

steshaw

;;
;; MobileOrg on iPad using Dropbox
;;

;; Settings basically copied from the screen cast, they differ
;; on the `org-mobile-inbox-for-pull` var wrt. the instructions
;; on the website.

;; - If MobileOrg is already linked to Dropbox. Unlink and delete
;;   the ~/Dropbox/MobileOrg folder.