Trac #9683: pretty_print clobbers _ (history)

After using `pretty_print`, the first history variable (`_`) no longer updates. {{{ ---------------------------------------------------------------------- | Sage Version 4.5.1, Release Date: 2010-07-19 | | Type notebook() for the GUI, and license() for information. | ---------------------------------------------------------------------- Loading Sage library. Current Mercurial branch is: combinat sage: 17 17 sage: _ 17 sage: 23 23 sage: _ 23 sage: pretty_print(17) <html><span class="math">\newcommand{\Bold}[1]{\mathbf{#1}}17</span></html> sage: _ 17 sage: 23 23 sage: _ 17 }}} The relevant function seems to be `pretty_print` in `/sage/misc/latex.py`, but I don't know the right way to fix it. The function and `pretty_print_default` in same file, and the functions `displayhook` and `install` in `/sage/misc/displayhook.py` may also be relevant. URL: http://trac.sagemath.org/9683 Reported by: mguaypaq Ticket author(s): Mike Hansen Reviewer(s): Volker Braun
sagemath · Apr 12, 2014 · a143cc0 · a143cc0
2 parents 3b94c5f + 3cc45a8
commit a143cc0
Showing 1 changed file with 6 additions and 2 deletions.
diff --git a/src/sage/misc/latex.py b/src/sage/misc/latex.py
@@ -2419,12 +2419,16 @@ def _show_s(s):
                 print MathJax().eval(tuple(s), mode='inline',
                         combine_all=True)
 
+    import __builtin__
+    in_ipython = hasattr(__builtin__, 'get_ipython')
     s = []
     for object in args:
         if object is None:
             continue
-        import __builtin__
-        __builtin__._=object
+        if in_ipython:
+            get_ipython().displayhook.update_user_ns(object)
+        else:
+            __builtin__._ = object
 
         from sage.plot.plot import Graphics
         from sage.plot.plot3d.base import Graphics3d