Factor str_type into hy.util

hy/compiler.py

@@ -33,7 +33,7 @@ from hy.models.list import HyList
 from hy.models.dict import HyDict
 from hy.models.keyword import HyKeyword
 
-from hy.util import flatten_literal_list
+from hy.util import flatten_literal_list, str_type
 
 from collections import defaultdict
 import codecs
@@ -949,10 +949,7 @@ class HyASTCompiler(object):
 
     @builds(HyKeyword)
     def compile_keyword(self, keyword):
-        _str_type = str
-        if sys.version_info[0] < 3:
-            _str_type = unicode
-        return ast.Str(s=_str_type(keyword), lineno=keyword.start_line,
+        return ast.Str(s=str_type(keyword), lineno=keyword.start_line,
                        col_offset=keyword.start_column)
 
     @builds(HyDict)

hy/models/keyword.py

@@ -20,20 +20,14 @@
 
 from __future__ import unicode_literals
 from hy.models import HyObject
-import sys
+from hy.util import str_type
 
 
-if sys.version_info[0] >= 3:
-    _str_type = str
-else:
-    _str_type = unicode
-
-
-class HyKeyword(HyObject, _str_type):
+class HyKeyword(HyObject, str_type):
     """Generic Hy Keyword object. It's either a ``str`` or a ``unicode``,
     depending on the Python version.
     """
 
     def __new__(cls, value):
-        obj = _str_type.__new__(cls, "\uFDD0" + value)
+        obj = str_type.__new__(cls, "\uFDD0" + value)
         return obj

hy/models/string.py

@@ -19,13 +19,7 @@
 # DEALINGS IN THE SOFTWARE.
 
 from hy.models import HyObject
-import sys
-
-
-if sys.version_info[0] >= 3:
-    str_type = str
-else:
-    str_type = unicode
+from hy.util import str_type
 
 
 class HyString(HyObject, str_type):

hy/util.py

@@ -18,6 +18,14 @@
 # FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 # DEALINGS IN THE SOFTWARE.
 
+import sys
+
+
+if sys.version_info[0] >= 3:
+    str_type = str
+else:
+    str_type = unicode
+
 
 def flatten_literal_list(entry):
     for e in entry: