lspitzner

{-# LANGUAGE Arrows, TemplateHaskell #-}


module Main where


import Prelude hiding (id, init, (.))
import Control.Arrow
import Control.Category

lspitzner

-- a djinn environment that encodes an instance of the
-- post correspondence problem. it requires recursive data
-- types.

data Foo a b x y = Foo (Bar a b (a x) (b (a (a y))))
                       (Bar a b (a (b x)) (a (a y)))
                       (Bar a b (b (b (a x))) (b (b y)))
 
-- we need duplicate to enforce N>=1
data Bar a b x y = Bar (Bar a b (a x) (b (a (a y))))

lspitzner

module Main where

import Control.Monad.Trans.Writer
import Data.Monoid ( Sum(..) )

f :: Writer (Sum Int) ()
f = undefined

g :: Writer (Sum Int) Int
g = do

lspitzner

#!/bin/bash
cabal list --simple-output | sed "s/ .*//" | uniq | xargs cabal info -v | grep "^        [^ ]" | sed "s/        //" | sed "s/\..*//" | sort | uniq -c | sort -bgr
# or full module names via
#cabal list --simple-output | sed "s/ .*//" | uniq | xargs cabal info -v | grep "^        [^ ]" | sed "s/        //" | sort
# (cannot post the latter; gists seem to have length limit on what you can paste :D)

lspitzner

{-# LANGUAGE GADTs #-}
{-# LANGUAGE TypeFamilies #-}
{-# LANGUAGE DataKinds #-}
{-# LANGUAGE TypeOperators #-}
{-# OPTIONS_GHC -Wall #-}

module Main where

data HList :: [*] -> * where
  HNil :: HList '[]

lspitzner

The most common thing is to install a library (so your project can use it) or
an executable (like when you install `hoogle` so you can search documentation
locally). Behind the scenes, this involves a number of steps:

1. determine package version plan (a consistent Set (Library,Version))
2. download dependencies (i.e. their source)
3. install dependencies (i.e. do steps 1-6a for each dependency)
4. configure (think: what to build in which order, with which compiler flags etc.)
5. build
6a. register (libraries) in package repository

lspitzner

Running 2 test suites...
Test suite unit-tests: RUNNING...
Test suite unit-tests: PASS
Test suite logged to: dist/test/Cabal-1.25.0.0-unit-tests.log
Test suite package-tests: RUNNING...
package-tests: We couldn't understand the build configuration.  Try editing Cabal.cabal to have 'build-type: Custom' and then rebuild
ing, or manually specifying CABAL_PACKAGETESTS_* environment variables (see README.md for more details).

Original error: Saved package config file body is corrupt. Try re-running the 'configure' command.
Test suite package-tests: FAIL

lspitzner

#!/bin/bash

ls -1 stackage | xargs -I{} bash -c "find \"stackage/{}\" -type f -name \"*.hs\" -o -name \"*.lhs\"\
  | xargs grep -h \"^import\" \
  | grep \" as \" \
  | sed \"s/ \+as//\" \
  | sed \"s/^import \+\(qualified \+\)\?//\" \
  | sort \
  | uniq \
  " \

lspitzner

old-style	new-style
install --only-dependencies	part of new-build
install path-to-local-dir	add a ./cabal.project file, add your local dependency, then use new-build (cabal.project syntax is described in the announcement)
install path-to-local-sdist	does not exist yet
install remote-package-uri	does not exist yet
install [--bindir=..]	does not exist (yet)
configure	new-configure
build	(part of) new-build
clean	does not exist yet; you have to remove ./dist-newstyle/ and ./cabal.project.local by hand, and potentially ./dist/ as well, i may have observed that it got touched by new-build (not sure, really). This needs to be done for each package referenced from the cabal.project as well.

lspitzner

import Distribution.Simple
import Distribution.PackageDescription
import Distribution.Simple.Program
import Distribution.Simple.Command
import Distribution.Simple.PreProcess
import Distribution.Simple.Setup
import Distribution.Simple.LocalBuildInfo
import Distribution.Simple.BuildPaths
import Distribution.Simple.BuildTarget
import System.Process