diff --git a/osh/types.asdl b/osh/types.asdl
@@ -0,0 +1,21 @@
+-- Types that don't depend on Id.  (To break dependency)
+
+module types {
+  -- Also invalid because of duplicate 'Path' -- to fix
+  -- bool_operand_type = Undefined | Path | Int | Str | Other
+  redir_type = Path | Desc | Here
+
+  -- Fifteen lexer modes for osh.
+  -- Possible additional modes:
+  --   nested backticks: echo `echo \`echo foo\` bar`
+  lex_mode =
+    NONE
+  | COMMENT
+  | OUTER
+  | DBRACKET
+  | SQ | DQ | DOLLAR_SQ
+  | ARITH
+  | EXTGLOB
+  | VS_1 | VS_2 | VS_ARG_UNQ | VS_ARG_DQ
+  | BASH_REGEX | BASH_REGEX_CHARS
+}
diff --git a/osh/word_parse.py b/osh/word_parse.py
@@ -18,11 +18,11 @@
 from core import util

 from osh import arith_parse
-from osh.meta import ast
+from osh.meta import ast, types

 word_part_e = ast.word_part_e
 word_e = ast.word_e
-lex_mode_e = ast.lex_mode_e
+lex_mode_e = types.lex_mode_e

 p_die = util.p_die
 log = util.log
diff --git a/osh/word_parse_test.py b/osh/word_parse_test.py
@@ -14,17 +14,16 @@
 from asdl import const

 from core import alloc
-from osh.meta import Id
 from core import test_lib
 from core import word

-from osh.meta import ast
+from osh.meta import ast, Id, types
 from osh import ast_lib
 from osh import parse_lib
 from osh.word_parse import WordParser  # module under test

 arith_expr_e = ast.arith_expr_e
-lex_mode_e = ast.lex_mode_e
+lex_mode_e = types.lex_mode_e


 def _InitWordParserWithArena(s):