Enable direnv bash hook if program is found

script_helpers/core.sh

@@ -11,3 +11,13 @@ abort() {
   exit 1
 }
 
+# Use this by setting a trap in your script, like so:
+# `trap at_exit EXIT`
+at_exit() {
+    ret=$?
+    if [[ $ret -gt 0 ]]; then
+      error "The script failed with error $ret.\n"
+    fi
+    exit "$ret"
+}
+