Improve history API docs

IPython/core/history.py

@@ -29,6 +29,7 b' import threading'
 # Our own packages
 from IPython.config.configurable import Configurable
 from IPython.external.decorator import decorator
+from IPython.utils.decorators import undoc
 from IPython.utils.path import locate_profile
 from IPython.utils import py3compat
 from IPython.utils.traitlets import (
@@ -40,6 +41,7 b' from IPython.utils.warn import warn'
 # Classes and functions
 #-----------------------------------------------------------------------------
 
+@undoc
 class DummyDB(object):
     """Dummy DB that will act as a black hole for history.
     
@@ -59,7 +61,7 b' class DummyDB(object):'
 
 @decorator
 def needs_sqlite(f, self, *a, **kw):
-    """return an empty list in the absence of sqlite"""
+    """Decorator: return an empty list in the absence of sqlite."""
     if sqlite3 is None or not self.enabled:
         return []
     else:
@@ -69,6 +71,7 b' def needs_sqlite(f, self, *a, **kw):'
 if sqlite3 is not None:
     DatabaseError = sqlite3.DatabaseError
 else:
+    @undoc
     class DatabaseError(Exception):
         "Dummy exception when sqlite could not be imported. Should never occur."
 
@@ -159,7 +162,7 b' class HistoryAccessor(Configurable):'
         hist_file : str
           Path to an SQLite history database stored by IPython. If specified,
           hist_file overrides profile.
-        config :
+        config : :class:`~IPython.config.loader.Config`
           Config object. hist_file can also be set through this.
         """
         # We need a pointer back to the shell for various tasks.
@@ -254,8 +257,8 b' class HistoryAccessor(Configurable):'
 
     @needs_sqlite
     @catch_corrupt_db
-    def get_session_info(self, session=0):
-        """get info about a session
+    def get_session_info(self, session):
+        """Get info about a session.
 
         Parameters
         ----------
@@ -383,6 +386,7 b' class HistoryAccessor(Configurable):'
 
         Returns
         -------
+        entries
         An iterator over the desired lines. Each line is a 3-tuple, either
         (session, line, input) if output is False, or
         (session, line, (input, output)) if output is True.
@@ -545,14 +549,14 b' class HistoryManager(HistoryAccessor):'
     # Methods for retrieving history
     # ------------------------------
     def get_session_info(self, session=0):
-        """get info about a session
+        """Get info about a session.
 
         Parameters
         ----------
 
         session : int
             Session number to retrieve. The current session is 0, and negative
-            numbers count back from current session, so -1 is previous session.
+            numbers count back from current session, so -1 is the previous session.
 
         Returns
         -------
@@ -616,6 +620,7 b' class HistoryManager(HistoryAccessor):'
             
         Returns
         -------
+        entries
         An iterator over the desired lines. Each line is a 3-tuple, either
         (session, line, input) if output is False, or
         (session, line, (input, output)) if output is True.
@@ -632,7 +637,7 b' class HistoryManager(HistoryAccessor):'
     ## ----------------------------
     def store_inputs(self, line_num, source, source_raw=None):
         """Store source and raw input in history and create input cache
-        variables _i*.
+        variables ``_i*``.
 
         Parameters
         ----------
@@ -803,7 +808,7 b' def extract_hist_ranges(ranges_str):'
 
     Examples
     --------
-    list(extract_input_ranges("~8/5-~7/4 2"))
+    >>> list(extract_input_ranges("~8/5-~7/4 2"))
     [(-8, 5, None), (-7, 1, 4), (0, 2, 3)]
     """
     for range_str in ranges_str.split():