Add support for sub-interpreters

Includes support for aliases in sub-interp
These are not identical to Tcl interp, but are conceptually very similar

For example:

  set i [interp]
  $i alias localcmd parentcmd arg1
  $i eval { localcmd x }

Invokes: parentcmd arg1 x

Signed-off-by: Steve Bennett <steveb@workware.net.au>

1 files changed, 1 insertions, 0 deletions

diff --git a/auto.def b/auto.def
index bb50330..624d6a3 100644
--- a/auto.def
+++ b/auto.def
@@ -242,6 +242,7 @@ dict set extdb attrs {
     file      {}
     glob      { tcl }
     history   {}
+    interp    { }
     load      { static }
     mk        { cpp optional }
     namespace { static }