On 2/15/2011 10:19 AM Chris Rebert said...
On Tue, Feb 15, 2011 at 7:17 AM, Jorge Vargas<jorge.var...@gmail.com> wrote:
Hello,
I have the following situation. In a big project that involves many
dependencies (and sadly some sys.module hacks) we have a bug, and it
will really help if i could monitor all changes made to that variable.
Is there a way to trace those changes ?
Is the variable's value of a mutable or immutable type? What is the
variable's scope (e.g. module-level global, or object attribute)? Is
the variable subject to getting rebound to an entirely new
value/object?
The answers to these questions will determine how much work will be
required to trace "changes" to the variable. I know of no built-in way
to directly do such a thing, but the underlying functionality
necessary to implement such a feature (e.g. sys.settrace,
__getattribute__, __setattr__) does exist.
Out of curiosity, if it's immutable, what approach might you try to
capture/trace reassignment? I've got a toy tracer that breaks with
simple assignment:
>>> A=tracer(3)
>>> A
3
>>> A+=3
value changed by 3 by add
>>> A
6
>>> B=A+6
value changed by 6 by add
>>> B
12
>>> B+=3
value changed by 3 by add
>>> B
15
>>> A = 4
>>> A+=4
>>>
Emile
--
http://mail.python.org/mailman/listinfo/python-list
