The purpose of this document is to specify a baseline set of functional programming features that users can request and that programming languages can advertise support for. This feature set strives to be "JSON-like" and "purely functional".
The goals of this specification are (in descending order of importance):
| // Which of f or g are more readable, and if possible, why? | |
| def f(x: Seq[Int]): Int = | |
| x.toList match { | |
| case Nil => 99 | |
| case lst => lst.sum | |
| } | |
| def g(x: Seq[Int]): Int = | |
| x.toList match { |
| -- show running queries (pre 9.2) | |
| SELECT procpid, age(clock_timestamp(), query_start), usename, current_query | |
| FROM pg_stat_activity | |
| WHERE current_query != '<IDLE>' AND current_query NOT ILIKE '%pg_stat_activity%' | |
| ORDER BY query_start desc; | |
| -- show running queries (9.2) | |
| SELECT pid, age(clock_timestamp(), query_start), usename, query | |
| FROM pg_stat_activity | |
| WHERE query != '<IDLE>' AND query NOT ILIKE '%pg_stat_activity%' |
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Total (non-error-throwing) lambda-calculus evaluators.
| { pkgs ? import <nixpkgs> {} }: | |
| let | |
| haskell = import (builtins.fetchTarball https://github.com/input-output-hk/haskell.nix/archive/master.tar.gz) { inherit pkgs; }; | |
| happyHack = config: | |
| let inherit (config.hsPkgs) happy; | |
| in "export happy_datadir=${happy.components.exes.happy}/share/${builtins.currentSystem}-ghc-${config.compiler.version}/${happy.identifier.name}-${happy.identifier.version}"; | |
| pkgSet = haskell.mkCabalProjectPkgSet { |
| #!/bin/bash | |
| if [ `id -u` -ne 0 ]; then | |
| echo "Rippling uninstall must be run by root" | |
| exit 1 | |
| fi | |
| sudo launchctl unload /Library/LaunchDaemons/com.rippling.* | |
| sudo rm -rf /Library/LaunchDaemons/com.rippling.* | |
| sudo rm -rf /opt/rippling |
| -- SYSTEM F | |
| -- http://homepages.inf.ed.ac.uk/slindley/papers/embedding-f.pdf | |
| -- | |
| -- Type-level lambdas | |
| -- https://gist.github.com/AndrasKovacs/ac71371d0ca6e0995541e42cd3a3b0cf | |
| {-# language TemplateHaskell, ScopedTypeVariables, RankNTypes, | |
| TypeFamilies, UndecidableInstances, DeriveFunctor, GADTs, | |
| TypeOperators, TypeApplications, AllowAmbiguousTypes, |
| public static class id extends Function { | |
| public Closure enter(StgContext context) { | |
| // context.R(2) is the first argument of the function | |
| // All id simply does is evaluate the argument - | |
| // it cannot do much more! | |
| return context.R(2).evaluate(context); | |
| } | |
| public int arity() { return 1; } | |
| } |