double quotes node identifiers

diff --git a/components/extlib/graphvizPp.ml b/components/extlib/graphvizPp.ml
index 18ebd94d9fb690f3c0749a3fef4514022fd3c0dd..aa472f76982945843304c7e1a3e589d17f4350ed 100644 (file)
--- a/components/extlib/graphvizPp.ml
+++ b/components/extlib/graphvizPp.ml
@@ -47,11 +47,11 @@ module Dot =
 
     let header ?(name = "g") fmt = fprintf fmt "@[<hv2>digraph %s {@," name
     let node name ?(attrs = []) fmt =
-      fprintf fmt "@[<hov2>%s@ [" name;
+      fprintf fmt "@[<hov2>\"%s\"@ [" name;
       attributes attrs fmt;
       fprintf fmt "];@]@,"
     let edge name1 name2 ?(attrs = []) fmt =
-      fprintf fmt "@[<hov2>%s ->@ %s@ [" name1 name2;
+      fprintf fmt "@[<hov2>\"%s\" ->@ \"%s\"@ [" name1 name2;
       attributes attrs fmt;
       fprintf fmt "];@]@,"
     let raw s fmt = pp_print_string fmt s