Don't let HySymbol inherit from HyString

NEWS.rst

@@ -33,6 +33,7 @@ Other Breaking Changes
 * `hy-repr` uses registered functions instead of methods
 * `HyKeyword` no longer inherits from the string type and has been
   made into its own object type.
+* `HySymbol` no longer inherits from `HyString`.
 * `(except)` is no longer allowed. Use `(except [])` instead.
 * `(import [foo])` is no longer allowed. Use `(import foo)` instead.
 

docs/language/internals.rst

@@ -119,13 +119,12 @@ the following order:
 HyString
 ~~~~~~~~
 
-``hy.models.HyString`` is the base class of string-equivalent Hy
-models. It also represents string literals (including bracket strings), which
-compile down to unicode string literals in Python. ``HyStrings`` inherit
-unicode objects in Python 2, and string objects in Python 3 (and are
-therefore not encoding-dependent).
+``hy.models.HyString`` represents string literals (including bracket strings),
+which compile down to unicode string literals in Python. ``HyStrings`` inherit
+unicode objects in Python 2, and string objects in Python 3 (and are therefore
+not encoding-dependent).
 
-``HyString`` based models are immutable.
+``HyString``\s are immutable.
 
 Hy literal strings can span multiple lines, and are considered by the
 parser as a single unit, respecting the Python escapes for unicode
@@ -163,8 +162,9 @@ valid numeric python literals will be turned into their Hy counterpart.
 HySymbol
 ~~~~~~~~
 
-``hy.models.HySymbol`` is the model used to represent symbols
-in the Hy language. It inherits :ref:`HyString`.
+``hy.models.HySymbol`` is the model used to represent symbols in the Hy
+language. Like ``HyString``, it inherits from ``str`` (or ``unicode`` on Python
+2).
 
 Symbols are :ref:`mangled <mangling>` when they are compiled
 to Python variable names.

hy/compiler.py

@@ -1298,7 +1298,7 @@ class HyASTCompiler(object):
                               "Can't assign to a callable: `%s'" % str_name)
 
         if (result.temp_variables
-                and isinstance(name, HyString)
+                and isinstance(name, HySymbol)
                 and '.' not in name):
             result.rename(name)
             # Throw away .expr to ensure that (setv ...) returns None.

hy/models.py

@@ -109,13 +109,13 @@ class HyBytes(HyObject, bytes_type):
 _wrappers[bytes_type] = HyBytes
 
 
-class HySymbol(HyString):
+class HySymbol(HyObject, str_type):
     """
-    Hy Symbol. Basically a String.
+    Hy Symbol. Basically a string.
     """
 
-    def __init__(self, string):
-        self += string
+    def __new__(cls, s=None):
+        return super(HySymbol, cls).__new__(cls, s)
 
 _wrappers[bool] = lambda x: HySymbol("True") if x else HySymbol("False")
 _wrappers[type(None)] = lambda foo: HySymbol("None")