merge patch for [ticket:2208]. This still needs documentation.

diff --cc CHANGES
index 8fba962d4e03e3b5eaef50801b65cfb69186d6fa,88ddad8f8f38c33493ff6d375b96e663d1f9e004..44f7a94f9e1d6be14893df59adf78f2430329aa0
--- 1/CHANGES
--- 2/CHANGES
+++ b/CHANGES
@@@ -3,41 -3,9 +3,52 @@@
  =======
  CHANGES
  =======
 -0.7.7
 -=====
 +0.7.7 - 0.7.xx
 +==============
 +
 +Changes which apply to 0.7.7 and subsequent versions of 0.7
 +are listed in the CHANGES file within the 0.7 branch.  All
 +those changes which are also in the 0.8 series (which is typically
 +all of them) are listed inline within the 0.8 changes above,
 +those which apply to an 0.7 release are noted.
 +
 +0.8.0b1
 +=======
  - orm
 +  - [feature] Major rewrite of relationship() 
 +    internals now allow join conditions which
 +    include columns pointing to themselves
 +    within composite foreign keys.   A new
 +    API for very specialized primaryjoin conditions
 +    is added, allowing conditions based on 
 +    SQL functions, CAST, etc. to be handled
 +    by placing the annotation functions
 +    remote() and foreign() inline within the
 +    expression when necessary.  Previous recipes
 +    using the semi-private _local_remote_pairs
 +    approach can be upgraded to this new 
 +    approach. [ticket:1401]
 +
++  - [feature] Added new core function "inspect()", 
++    which serves as a generic gateway to
++    introspection into mappers, objects,
++    others.   The Mapper and InstanceState
++    objects have been enhanced with a public
++    API that allows inspection of mapped 
++    attributes, including filters for column-bound
++    or relationship-bound properties, inspection
++    of current object state, history of
++    attributes, etc.  [ticket:2208]
++
 +  - [feature] Query now "auto correlates" by 
 +    default in the same way as select() does.
 +    Previously, a Query used as a subquery
 +    in another would require the correlate()
 +    method be called explicitly in order to 
 +    correlate a table on the inside to the
 +    outside.  As always, correlate(None)
 +    disables correlation.  [ticket:2179]
 +
    - [feature] Added prefix_with() method
      to Query, calls upon select().prefix_with()
      to allow placement of MySQL SELECT
@@@ -77,9 -27,8 +88,13 @@@
    - [bug] Fixed bug which would prevent
      OrderingList from being pickleable
      [ticket:2454].  Courtesy Jeff Dairiki
 +    also in 0.7.7.
  
  - sql
++  - [feature] The Inspector object can now be 
++    acquired using the new inspect() service,
++    part of [ticket:2208]
++
    - [bug] Removed warning when Index is created
      with no columns; while this might not be what 
      the user intended, it is a valid use case 

diff --cc lib/sqlalchemy/__init__.py
index 962a1a761bf18e52a6fe2303c39b58b3d596f629,ee7bf4c6f9bd9eddcb9004fc7fbf67dc55a3eff5..422d9e43e8b43ca717d8f7b8f9aa01a99150025f
--- 1/lib/sqlalchemy/__init__.py
--- 2/lib/sqlalchemy/__init__.py
+++ b/lib/sqlalchemy/__init__.py
@@@ -115,11 -117,11 +117,11 @@@ from sqlalchemy.engine import create_en
  
  
  __all__ = sorted(name for name, obj in locals().items()
-                  if not (name.startswith('_') or inspect.ismodule(obj)))
+                  if not (name.startswith('_') or _inspect.ismodule(obj)))
  
 -__version__ = '0.7.7'
 +__version__ = '0.8.0b1'
  
- del inspect, sys
+ del _inspect, sys
  
  from sqlalchemy import util as _sa_util
  _sa_util.importlater.resolve_all()

diff --cc lib/sqlalchemy/orm/attributes.py
index ec0b84a60d8f523766f0a3b65db22fa385a2a464,c351748df4267431905a304e7379abca80dfd571..d756824439896996d25dff7fc7f532dd491ae00c
--- 1/lib/sqlalchemy/orm/attributes.py
--- 2/lib/sqlalchemy/orm/attributes.py
+++ b/lib/sqlalchemy/orm/attributes.py
@@@ -22,79 -22,61 +22,78 @@@ from sqlalchemy.orm import interfaces, 
  
  mapperutil = util.importlater("sqlalchemy.orm", "util")
  
 -PASSIVE_NO_RESULT = util.symbol('PASSIVE_NO_RESULT')
 -ATTR_WAS_SET = util.symbol('ATTR_WAS_SET')
 -ATTR_EMPTY = util.symbol('ATTR_EMPTY')
 -NO_VALUE = util.symbol('NO_VALUE')
 -NEVER_SET = util.symbol('NEVER_SET')
 -
 -PASSIVE_RETURN_NEVER_SET = util.symbol('PASSIVE_RETURN_NEVER_SET',
 -"""Symbol indicating that loader callables can be 
 -fired off, but if no callable is applicable and no value is
 -present, the attribute should remain non-initialized.
 -NEVER_SET is returned in this case.
 -""")
 -
 -PASSIVE_NO_INITIALIZE = util.symbol('PASSIVE_NO_INITIALIZE',
 -"""Symbol indicating that loader callables should
 -   not be fired off, and a non-initialized attribute 
 -   should remain that way.
 -""")
 -
 -PASSIVE_NO_FETCH = util.symbol('PASSIVE_NO_FETCH',
 -"""Symbol indicating that loader callables should not emit SQL, 
 -   but a value can be fetched from the current session.
 -   
 -   Non-initialized attributes should be initialized to an empty value.
 +PASSIVE_NO_RESULT = util.symbol('PASSIVE_NO_RESULT',
 +"""Symbol returned by a loader callable or other attribute/history
 +retrieval operation when a value could not be determined, based
 +on loader callable flags.
 +"""
 +)
  
 +ATTR_WAS_SET = util.symbol('ATTR_WAS_SET',
 +"""Symbol returned by a loader callable to indicate the
 +retrieved value, or values, were assigned to their attributes
 +on the target object.
  """)
  
 -PASSIVE_NO_FETCH_RELATED = util.symbol('PASSIVE_NO_FETCH_RELATED',
 -"""Symbol indicating that loader callables should not emit SQL for
 -   loading a related object, but can refresh the attributes of the local
 -   instance in order to locate a related object in the current session.
 -   
 -   Non-initialized attributes should be initialized to an empty value.
 -   
 -   The unit of work uses this mode to check if history is present
 -   on many-to-one attributes with minimal SQL emitted.
 -
 +ATTR_EMPTY = util.symbol('ATTR_EMPTY',
 +"""Symbol used internally to indicate an attribute had no callable.
  """)
  
 -PASSIVE_ONLY_PERSISTENT = util.symbol('PASSIVE_ONLY_PERSISTENT',
 -"""Symbol indicating that loader callables should only fire off for
 -   parent objects which are persistent (i.e., have a database
 -   identity).
 -
 -   Load operations for the "previous" value of an attribute make
 -   use of this flag during change events.
 -
 -""")
 +NO_VALUE = util.symbol('NO_VALUE',
 +"""Symbol which may be placed as the 'previous' value of an attribute,
 +indicating no value was loaded for an attribute when it was modified,
 +and flags indicated we were not to load it.
 +"""
 +)
  
 -PASSIVE_OFF = util.symbol('PASSIVE_OFF',
 -"""Symbol indicating that loader callables should be executed
 -   normally.
 +NEVER_SET = util.symbol('NEVER_SET',
 +"""Symbol which may be placed as the 'previous' value of an attribute
 +indicating that the attribute had not been assigned to previously.
 +"""
 +)
 +
 +CALLABLES_OK = util.symbol("CALLABLES_OK",
 +"""Loader callables can be fired off if a value
 +is not present.""", canonical=1
 +)
 +
 +SQL_OK = util.symbol("SQL_OK",
 +"""Loader callables can emit SQL at least on scalar value
 +attributes.""", canonical=2)
 +
 +RELATED_OBJECT_OK = util.symbol("RELATED_OBJECT_OK",
 +"""callables can use SQL to load related objects as well
 +as scalar value attributes.
 +""", canonical=4
 +)
 +
 +INIT_OK = util.symbol("INIT_OK",
 +"""Attributes should be initialized with a blank
 +value (None or an empty collection) upon get, if no other
 +value can be obtained.
 +""", canonical=8
 +)
 +
 +NON_PERSISTENT_OK = util.symbol("NON_PERSISTENT_OK",
 +"""callables can be emitted if the parent is not persistent.""", 
 +canonical=16
 +)
 +
 +
 +# pre-packaged sets of flags used as inputs
 +PASSIVE_OFF = RELATED_OBJECT_OK | \
 +                NON_PERSISTENT_OK | \
 +                INIT_OK | \
 +                CALLABLES_OK | \
 +                SQL_OK
 +
 +PASSIVE_RETURN_NEVER_SET = PASSIVE_OFF  ^ INIT_OK
 +PASSIVE_NO_INITIALIZE = PASSIVE_RETURN_NEVER_SET ^ CALLABLES_OK
 +PASSIVE_NO_FETCH = PASSIVE_OFF ^ SQL_OK
 +PASSIVE_NO_FETCH_RELATED = PASSIVE_OFF ^ RELATED_OBJECT_OK
 +PASSIVE_ONLY_PERSISTENT = PASSIVE_OFF ^ NON_PERSISTENT_OK
  
 -""")
  
- 
  class QueryableAttribute(interfaces.PropComparator):
      """Base class for class-bound attributes. """
  

diff --cc lib/sqlalchemy/orm/dynamic.py
Simple merge

diff --cc lib/sqlalchemy/orm/mapper.py
Simple merge

diff --cc lib/sqlalchemy/orm/properties.py
Simple merge

diff --cc lib/sqlalchemy/orm/state.py
index 30a08faba007ae0c455bfe3d2b80722662308901,a8c9dea06c9fd9ac30ebbd078825caea727f13b9..64fca87156adfa9d92fb472e191afc456cac43d3
--- 1/lib/sqlalchemy/orm/state.py
--- 2/lib/sqlalchemy/orm/state.py
+++ b/lib/sqlalchemy/orm/state.py
@@@ -17,13 -17,15 +17,13 @@@ from sqlalchemy import uti
  
  from sqlalchemy.orm import exc as orm_exc, attributes, interfaces,\
          util as orm_util
--from sqlalchemy.orm.attributes import PASSIVE_OFF, PASSIVE_NO_RESULT, \
-     SQL_OK, NEVER_SET, ATTR_WAS_SET, NO_VALUE
 -    PASSIVE_NO_FETCH, NEVER_SET, ATTR_WAS_SET, NO_VALUE,\
++from sqlalchemy.orm.attributes import PASSIVE_NO_RESULT, \
++    SQL_OK, NEVER_SET, ATTR_WAS_SET, NO_VALUE,\
+     PASSIVE_NO_INITIALIZE
  
  mapperlib = util.importlater("sqlalchemy.orm", "mapperlib")
- 
- import sys
+ sessionlib = util.importlater("sqlalchemy.orm", "session")
  
 -import sys
 -
  class InstanceState(object):
      """tracks state information at the instance level."""
  

diff --cc lib/sqlalchemy/orm/util.py
Simple merge

diff --cc test/orm/test_mapper.py
Simple merge

diff --cc test/orm/test_query.py
Simple merge