Add a bootstrap-haskell script, fixes #36

README.md

@@ -19,6 +19,24 @@ Similar in scope to [rustup](https://github.com/rust-lang-nursery/rustup.rs), [p
 
 ## Installation
 
+### Simple bootstrap of ghcup, GHC and cabal-install
+
+```sh
+# complete bootstrap
+curl https://raw.githubusercontent.com/haskell/ghcup/master/bootstrap-haskell -sSf | sh
+
+# prepare your environment
+. "$HOME/.ghcup/env"
+echo '. $HOME/.ghcup/env' >> "$HOME/.bashrc" # or similar
+
+# now create a project, such as:
+mkdir myproject && cd myproject
+cabal init -n --is-executable
+cabal v2-run
+```
+
+### Manual install
+
 Just place the `ghcup` shell script into your `PATH` anywhere.
 
 E.g.:

bootstrap-haskell

+#!/bin/sh
+
+# safety subshell to avoid executing anything in case this script is not downloaded properly
+(
+
+die() {
+    (>&2 printf "\\033[0;31m%s\\033[0m\\n" "$1")
+    exit 2
+}
+
+edo()
+{
+	printf "\\033[0;35m%s\\033[0m\\n" "$*"
+    "$@" || exit 2
+}
+
+echo
+echo "Welcome to Haskell!"
+echo
+echo "This will download and install the Glasgow Haskell Compiler (GHC) for "
+echo "the Haskell programming language, and the Cabal build tool."
+echo
+echo "It will add the 'cabal', 'ghc', and 'ghcup' executables to bin directory "
+echo "located at: "
+echo
+echo "  $HOME/.ghcup/bin"
+echo
+echo "and create the environment file $HOME/.ghcup/env"
+echo "which you should source in your ~/.bashrc or similar to get the required"
+echo "PATH components."
+echo
+
+if [ -z "${BOOTSTRAP_HASKELL_NONINTERACTIVE}" ] ; then
+	echo "To proceed with the installation press enter, to cancel press ctrl-c."
+	echo "Note that this script can be re-run at any given time."
+	echo
+
+	# Wait for user input to continue.
+	# shellcheck disable=SC2034
+	read -r answer </dev/tty
+fi
+
+edo mkdir -p "${HOME}"/.ghcup/bin
+
+if command -V "ghcup" >/dev/null 2>&1 ; then
+	if [ -z "${BOOTSTRAP_HASKELL_NO_UPGRADE}" ] ; then
+		edo ghcup upgrade
+	fi
+else
+	edo curl https://raw.githubusercontent.com/haskell/ghcup/master/ghcup > "${HOME}"/.ghcup/bin/ghcup
+	edo chmod +x "${HOME}"/.ghcup/bin/ghcup
+
+	cat <<-EOF > "${HOME}"/.ghcup/env || die "Failed to create env file"
+		export PATH="\$HOME/.cabal/bin:\$HOME/.ghcup/bin:\$PATH"
+		EOF
+	# shellcheck disable=SC1090
+	edo . "${HOME}"/.ghcup/env
+fi
+
+edo ghcup install
+
+edo ghcup set
+edo ghcup install-cabal
+
+edo cabal new-update
+edo cabal new-install --symlink-bindir="$HOME/.cabal/bin" cabal-install
+
+printf "\\033[0;35m%s\\033[0m\\n" ""
+printf "\\033[0;35m%s\\033[0m\\n" "Installation done!"
+printf "\\033[0;35m%s\\033[0m\\n" ""
+printf "\\033[0;35m%s\\033[0m\\n" "Don't forget to source $HOME/.ghcup/env in your ~/.bashrc or similar."
+printf "\\033[0;35m%s\\033[0m\\n" ""
+
+
+)

ghcup

@@ -245,7 +245,7 @@ FLAGS:
     -h, --help       Prints help information
 
 ARGS:
-    [VERSION|TAG]    E.g. \"8.4.3\" or \"8.6.1\" or
+    [VERSION|TAG]    E.g. \"8.4.3\" or \"8.6.3\" or
                      a tag like \"recommended\" or \"latest\"
                      (default: discovers recommended version)