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Questions tagged [haskell-platform]

The Haskell Platform is a standardized multi-OS distribution for the Haskell programming language. Questions on this tag should not be about the Haskell language in general, but specific to issues with the platform installer and distribution.

The Haskell Platform is a standardized multi-OS distribution for the Haskell programming language that includes the ghc compiler, as well as the cabal-install and stack build tools, and a core set of libraries. It was introduced in 2008 as a project to standardize the Haskell library environment and installation process.

It currently ships in two distributions -- "core," which is recommended, and only includes ghc-bundled libraries, and "full" which comes with a larger collection of libraries preinstalled into the global package database.

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How to read this GHC Core "proof"?

I wrote this small bit of Haskell to figure out how GHC proves that for natural numbers, you can only halve the even ones: {-# LANGUAGE DataKinds, GADTs, KindSignatures, TypeFamilies #-} module Nat where data Nat = Z | S Nat data Parity = Even |…
Mathijs Kwik
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Haskell program outputs `<>`

I wrote a Haskell program that preforms a binary search on a list. At least that's what I thought it does. When I compiled the program with ghc v7.6.3 and ran the program I got the following output: progname: <> What on earth does this output…
recursion.ninja
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How do I create an operator in Haskell?

Making a ternary logic table, and I would like to make my own function for an operator that I'll call <=>. So, for example, I want to do this, but that isn't right. what's the correct way to do this? data Ternary = T | F | M deriving (Eq, Show,…
user1189352
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Haskell / GHCi - loading modules from different directories

My haskell application has the following directory structure: src/ utils/Utils.hs subsystem/Subsystem.hs The Subsystem module imports Utils module. I would like to hand test this code in GHCi. The problem is GHCi seems to be only looking…
simon
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Everywhere that GHC/Haskell Platform installs

Assume I want to completely reinstall GHC/HP. I want to (as much for superstition as anything) delete anything and everything from previous installs. What do I actually need to delete (and where)? Edit: I'm on OSX, but I'm more curious if this…
amindfv
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Installing & Building GHC with OSX Mavericks GHC

Why doesn't my GHC 7.6.3 work after upgrading to OSX Mavericks?
katychuang
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How to install Haskell (Platform or Stack) in 2018 on Linux?

I am trying to learn Haskell from the book Learn You a Haskell by Miran Lipovača. Both the book and haskell.org recommends installing the Haskell Platform but there is no download for Manjaro Linux (Arch based) which I use. I found this guide from…
Klorax
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Preferred way to do locales in the Haskell Platform

The Haskell platform includes two obsolete libraries, old-time and old-locale. For old-time, it also includes the preferred alternative (namely time), but I can't figure out what the recommended alternative for old-locale is. Is this simply a…
user355466
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Haskell library for HTTP communication

What is the recommended library for web client programming which involves HTTP requests. I know there is a package called HTTP but it doesn't seem to support HTTPS. Is there any better library for it ? I expect a library with functionality something…
Sibi
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Haskell platform: nested functions and optimization

There's a very common pattern in the implementation of many functions in the haskell platform that bothers me, but I wasn't able to find an explanation. It's about the use of nested functions for optimization. The reason for nested functions in…
Riccardo T.
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What are the most important abstractions in Haskell? Monads? Applicatives?

I want to know which libraries, functions, and concepts I definitely should know about and how to use. Monad and the functions there is the typical example, but there are other good primitives to use in coding, like Arrows, Applicative, ... Who are…
telephone
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What's the difference between GHC and the Haskell Platform?

I'm about to get into Haskell, and I'm a bit confused why I'm recommended to install both GHC and the Haskell-platform via brew. Isn't GHC a Haskell implementation/compiler? When does one need the platform?
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export from module

Here is a code taken from http://www.angelfire.com/tx4/cus/shapes/haskell98.html . It compiles and executes correctly in WinGHCi if I comment the names in the module header. But if the names are kept then it does not compile - it reports an error on…
R71
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What's the smoothest way to update haskell platform to latest?

I'm on OSX 10.6 and I have platform 2010.2.0.0 currently. Should I just install 2011.2.0.1 on top or is there an update mechanism that will be smoother?
Peter Hall
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Haskell reinstall base with profiling enabled

I am trying reinstall my Haskell libraries with profiling enabled by following the instructions listed here However, whenever cabal attempts to reinstall one of the libraries I get the following message: LibraryNameHere.hs:1:1: Could not find…
recursion.ninja
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