Script to switch swap Cabal sandboxes for different versions of GHC.

ghc-switch.sh

# swith out a cabal sandbox for one version of a compiler for another.

#!/bin/bash

set -e

if [ -z "$2" ]; then
  echo usage: $0 ghc-version-from ghc-version-to
  exit 1
fi

CONFIG=cabal.sandbox.config
SANDBOX=.cabal-sandbox

FROMCONFIG=$CONFIG-$1
FROMSANDBOX=$SANDBOX-$1

TOCONFIG=$CONFIG-$2
TOSANDBOX=$SANDBOX-$2

if [ -e "$TOCONFIG" ]; then
  if [ -d "$TOSANDBOX" ]; then
    rm -rf dist
    cp -r $SANDBOX   $FROMSANDBOX
    cp    $CONFIG    $FROMCONFIG
    cp -r $TOSANDBOX $SANDBOX
    cp    $TOCONFIG  $CONFIG
  else
    echo $TOSANDBOX
    exit 1
  fi
else
  echo $TOCONFIG or $TOSANDBOX do not exist
  exit 1
fi