creates a virtual environment for encorec

the idea is to create a virtual environment similar to what you
can expect in virtualenv (python) and/or rbenv (ruby). At the moment
it just sets the encore compiler to the right path. Therefore, forking
and having multiple copies of the repo with multiple compilers is
easy to handle. Steps involved:

  1. go to the encore compiler fork you would like to activate
  2. source activate
  3. from this terminal, you can compile any encore program and
     it will safely use the encore compiler that you jut activated.

missing features:

  - no real dependency management yet, so no need to create new folder

Author: Kiko Fernandez Reyes

activate

@@ -0,0 +1,76 @@
+# This file must be used with "source bin/activate" *from bash*
+# you cannot run it directly
+
+deactivate () {
+    # reset old environment variables
+    if [ -n "$_OLD_VIRTUAL_PATH" ] ; then
+        PATH="$_OLD_VIRTUAL_PATH"
+        export PATH
+        unset _OLD_VIRTUAL_PATH
+    fi
+    if [ -n "$_OLD_VIRTUAL_ENCORECHOME" ] ; then
+        ENCORECHOME="$_OLD_VIRTUAL_ENCORECHOME"
+        export ENCORECHOME
+        unset _OLD_VIRTUAL_ENCORECHOME
+    fi
+
+    # This should detect bash and zsh, which have a hash command that must
+    # be called to get it to forget past commands.  Without forgetting
+    # past commands the $PATH changes we made may not be respected
+    if [ -n "$BASH" -o -n "$ZSH_VERSION" ] ; then
+        hash -r 2>/dev/null
+    fi
+
+    if [ -n "$_OLD_VIRTUAL_PS1" ] ; then
+        PS1="$_OLD_VIRTUAL_PS1"
+        export PS1
+        unset _OLD_VIRTUAL_PS1
+    fi
+
+    unset ENCOREC_VIRTUAL_ENV
+    if [ ! "$1" = "nondestructive" ] ; then
+    # Self destruct!
+        unset -f deactivate
+    fi
+}
+
+# unset irrelevant variables
+deactivate nondestructive
+
+ENCOREC_VIRTUAL_ENV=$(pwd)
+export ENCOREC_VIRTUAL_ENV
+
+_OLD_VIRTUAL_PATH="$PATH"
+PATH="$ENCOREC_VIRTUAL_ENV/release:$PATH"
+export PATH
+
+# unset ENCORECHOME if set
+# this will fail if ENCORECHOME is set to the empty string (which is bad anyway)
+# could use `if (set -u; : $ENCORECHOME) ;` in bash
+if [ -n "$ENCORECHOME" ] ; then
+    _OLD_VIRTUAL_ENCORECHOME="$ENCORECHOME"
+    unset ENCORECHOME
+fi
+
+if [ -z "$ENCOREC_VIRTUAL_ENV_DISABLE_PROMPT" ] ; then
+    _OLD_VIRTUAL_PS1="$PS1"
+    if [ "x" != x ] ; then
+        PS1="$PS1"
+    else
+    if [ "`basename \"$ENCOREC_VIRTUAL_ENV\"`" = "__" ] ; then
+        # special case for Aspen magic directories
+        # see http://www.zetadev.com/software/aspen/
+        PS1="[`basename \`dirname \"$ENCOREC_VIRTUAL_ENV\"\``] $PS1"
+    else
+        PS1="(`basename \"$ENCOREC_VIRTUAL_ENV\"`)$PS1"
+    fi
+    fi
+    export PS1
+fi
+
+# This should detect bash and zsh, which have a hash command that must
+# be called to get it to forget past commands.  Without forgetting
+# past commands the $PATH changes we made may not be respected
+if [ -n "$BASH" -o -n "$ZSH_VERSION" ] ; then
+    hash -r 2>/dev/null
+fi