On Wed, Nov 18, 2009 at 1:23 AM, Fernando Perez <fperez....@gmail.com> wrote: > On Tue, Nov 17, 2009 at 7:51 PM, William Stein <wst...@gmail.com> wrote: >> Can somebody referee this? It's mainly code in the *notebook* -- >> it doesn't seem possible to do something like the above on the command >> line without some deep internal change to Ipython. >> > > Actually no, not that hard: ipython executes all user code inside a
Awesome. I've made a new ticket for doing a command-line version for Sage: http://trac.sagemath.org/sage_trac/ticket/7486 and I've posted your email and code there. I will also try using a dictionary instead catching NameError's. I don't know if that will robustly work in all cases for the notebook, but we'll see. > dict created at initialization time. One could replace this (today a > plain python dict) with another dict that would implement the > requested behavior. This would spring variables into existence when a > KeyError was about to occur. > > The command-line doesn't have the notion of a cell (yet, that will > hopefully change soon) but it could be toggled with a function call. > > It's basically a matter of instantiating the initial ipython with a > custom user_ns dict that does the above, that should be all. And > providing a magic (or even plain) function in the global namespace to > toggle this behavior on/off at runtime. > > The attached file (run it as 'ipauto.py') shows how it could work, I > didn't implement the toggling and it's a quick hack, but the basic > idea is there. Here it is in action: > > In [1]: %autocall 0 > Automatic calling is: OFF > > In [2]: x+y > Injecting x > Injecting y > Out[2]: x + y > > In [3]: type(x) > Out[3]: <class 'sympy.core.symbol.Symbol'> > > In [4]: x+3 > Out[4]: 3 + x > > In [5]: x**2+x*x > Out[5]: 2*x**2 > > In [6]: x+z**3 > Injecting z > Out[6]: x + z**3 > > > A couple of notes: > > - It's key to disable autocalling for this to work, otherwise too many > false positives are triggered. If this idea proves to have wings, it > will be one more argument in favor of disabling autocalling (it just > has too many uncontrollable side effects). > In Sage autocall is disabled by default, since it is too confusing. > - Unfortunately IPython as shipped needs a tiny patch for this to > work, due to a really silly omission. The patch is a trivial 2-liner, > in case anyone wants to take this further for Sage: > > (ipython-0.10)maqroll[0.10]> bzr diff > === modified file 'IPython/Shell.py' > --- IPython/Shell.py 2009-04-14 20:12:02 +0000 > +++ IPython/Shell.py 2009-11-18 09:03:01 +0000 > @@ -1230,7 +1230,7 @@ > > > # This is the one which should be called by external code. > -def start(user_ns = None): > +def start(user_ns = None, user_global_ns = None): > """Return a running shell instance, dealing with threading options. > > This is a factory function which will instantiate the proper IPython shell > @@ -1238,7 +1238,7 @@ > different GUI toolkits require different thread handling details.""" > > shell = _select_shell(sys.argv) > - return shell(user_ns = user_ns) > + return shell(user_ns = user_ns, user_global_ns = user_global_ns) > > # Some aliases for backwards compatibility > IPythonShell = IPShell Thanks! -- William -- To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
