154 lines
4.9 KiB
Markdown
154 lines
4.9 KiB
Markdown
`ghcup` makes it easy to install specific versions of `ghc` on GNU/Linux,
|
|
macOS (aka Darwin) and FreeBSD and can also bootstrap a fresh Haskell developer environment from scratch.
|
|
It follows the unix UNIX philosophy of [do one thing and do it well](https://en.wikipedia.org/wiki/Unix_philosophy#Do_One_Thing_and_Do_It_Well).
|
|
|
|
Similar in scope to [rustup](https://github.com/rust-lang-nursery/rustup.rs), [pyenv](https://github.com/pyenv/pyenv) and [jenv](http://www.jenv.be).
|
|
|
|
*Ubuntu users may prefer [hvr's ppa](https://launchpad.net/~hvr/+archive/ubuntu/ghc).*
|
|
|
|
## Table of Contents
|
|
|
|
* [Installation](#installation)
|
|
* [Usage](#usage)
|
|
* [Manpages](#manpages)
|
|
* [Design goals](#design-goals)
|
|
* [How](#how)
|
|
* [Known users](#known-users)
|
|
* [Known problems](#known-problems)
|
|
* [FAQ](#faq)
|
|
|
|
## Installation
|
|
|
|
### Simple bootstrap
|
|
|
|
Follow the instructions at [https://www.haskell.org/ghcup/](https://www.haskell.org/ghcup/)
|
|
|
|
### Manual install
|
|
|
|
Download the binary for your platform at [https://downloads.haskell.org/~ghcup/](https://downloads.haskell.org/~ghcup/)
|
|
and place it into your `PATH` anywhere.
|
|
|
|
Then adjust your `PATH` in `~/.bashrc` (or similar, depending on your shell) like so:
|
|
|
|
```sh
|
|
export PATH="$HOME/.cabal/bin:$HOME/.ghcup/bin:$PATH"
|
|
```
|
|
|
|
## Usage
|
|
|
|
See `ghcup --help`.
|
|
|
|
Common use cases are:
|
|
|
|
```sh
|
|
# list available ghc/cabal versions
|
|
ghcup list
|
|
|
|
# install the recommended GHC version
|
|
ghcup install
|
|
|
|
# install a specific GHC version
|
|
ghcup install 8.2.2
|
|
|
|
# set the currently "active" GHC version
|
|
ghcup set 8.4.4
|
|
|
|
# install cabal-install
|
|
ghcup install-cabal
|
|
|
|
# update ghcup itself
|
|
ghcup upgrade
|
|
```
|
|
|
|
Generally this is meant to be used with [`cabal-install`](https://hackage.haskell.org/package/cabal-install), which
|
|
handles your haskell packages and can demand that [a specific version](https://cabal.readthedocs.io/en/latest/nix-local-build.html#cfg-flag---with-compiler) of `ghc` is available, which `ghcup` can do.
|
|
|
|
### Manpages
|
|
|
|
For man pages to work you need [man-db](http://man-db.nongnu.org/) as your `man` provider, then issue `man ghc`. Manpages only work for the currently set ghc.
|
|
`MANPATH` may be required to be unset.
|
|
|
|
### Bash-completion
|
|
|
|
Depending on your distro and setup, install `.bash-completion` from this repo
|
|
as e.g. `/etc/bash_completion.d/ghcup` and make sure your bashrc sources the
|
|
startup script (`/usr/share/bash-completion/bash_completion` on some distros).
|
|
|
|
## Design goals
|
|
|
|
1. simplicity
|
|
2. non-interactive
|
|
3. portable (eh)
|
|
4. do one thing and do it well (UNIX philosophy)
|
|
|
|
### Non-goals
|
|
|
|
1. invoking `sudo`, `apt-get` or *any* package manager
|
|
2. handling system packages
|
|
3. handling cabal projects
|
|
4. being a stack alternative
|
|
|
|
## How
|
|
|
|
Installs a specified GHC version into `~/.ghcup/ghc/<ver>`, and places `ghc-<ver>` symlinks in `~/.ghcup/bin/`.
|
|
|
|
Optionally, an unversioned `ghc` link can point to a default version of your choice.
|
|
|
|
This uses precompiled GHC binaries that have been compiled on fedora/debian by [upstream GHC](https://www.haskell.org/ghc/download_ghc_8_6_1.html#binaries).
|
|
|
|
Alternatively, you can also tell it to compile from source (note that this might fail due to missing requirements).
|
|
|
|
In addition this script can also install `cabal-install`.
|
|
|
|
## Known users
|
|
|
|
* [vabal](https://github.com/Franciman/vabal)
|
|
|
|
## Known problems
|
|
|
|
### Limited distributions supported
|
|
|
|
Currently only GNU/Linux distributions compatible with the [upstream GHC](https://www.haskell.org/ghc/download_ghc_8_6_1.html#binaries) binaries are supported.
|
|
|
|
### Precompiled binaries
|
|
|
|
Since this uses precompiled binaries you may run into
|
|
several problems.
|
|
|
|
#### Missing libtinfo (ncurses)
|
|
|
|
You may run into problems with *ncurses* and **missing libtinfo**, in case
|
|
your distribution doesn't use the legacy way of building
|
|
ncurses and has no compatibility symlinks in place.
|
|
|
|
Ask your distributor on how to solve this or
|
|
try to compile from source via `ghcup compile <version>`.
|
|
|
|
#### Libnuma required
|
|
|
|
This was a [bug](https://ghc.haskell.org/trac/ghc/ticket/15688) in the build system of some GHC versions that lead to
|
|
unconditionally enabled libnuma support. To mitigate this you might have to install the libnuma
|
|
package of your distribution. See [here](https://gitlab.haskell.org/haskell/ghcup/issues/58) for a discussion.
|
|
|
|
### Compilation
|
|
|
|
Although this script can compile GHC for you, it's just a very thin
|
|
wrapper around the build system. It makes no effort in trying
|
|
to figure out whether you have the correct toolchain and
|
|
the correct dependencies. Refer to [the official docs](https://ghc.haskell.org/trac/ghc/wiki/Building/Preparation/Linux)
|
|
on how to prepare your environment for building GHC.
|
|
|
|
## FAQ
|
|
|
|
1. Why reimplement stack?
|
|
|
|
ghcup is not a reimplementation of stack. The only common part is automatic installation of GHC, but even that differs in scope and design.
|
|
|
|
2. Why not support windows?
|
|
|
|
Consider using [Chocolatey](https://chocolatey.org/search?q=ghc) or [ghcups](https://github.com/kakkun61/ghcups).
|
|
|
|
3. Why the haskell reimplementation?
|
|
|
|
Why not?
|