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When saving, how can you check if a field has changed?
... try:
obj = sender.objects.get(pk=instance.pk)
except sender.DoesNotExist:
pass # Object is new, so field hasn't technically changed, but you may want to do something else here.
else:
if not obj.some_field == instance.some_field: # Field has changed
# do...
How do iOS Push Notifications work?
...t kind of connection always with APN service? If such is the case then how does APN service handle so many connections - If a server can hold 50k connections and there are 500 million users always, service at least needs 10000 servers right. Is this a practical scenario?
– AV94...
Checking Bash exit status of several commands efficiently
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Be advised that while this solution is the simplest, it does not let you perform any cleanup on failure.
– Josh J
Jun 19 '15 at 14:38
6
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Should a “static final Logger” be declared in UPPER-CASE?
...t think immutability is concerned with how the state changes, only that it does. moreover, what's a user? the external user running the program? would you make a distinction between state being modified by a user pressing a button, and it being modified by a timer firing at some random interval? (i ...
Set attribute without value
... knows it's a setter. The fact that passing an empty string works but null does not is somewhat surprising.
– Jon
Oct 31 '12 at 13:38
2
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Can you split a stream into two streams?
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Not exactly. You can't get two Streams out of one; this doesn't make sense -- how would you iterate over one without needing to generate the other at the same time? A stream can only be operated over once.
However, if you want to dump them into a list or something, you could do
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How do I create a message box with “Yes”, “No” choices and a DialogResult?
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'DialogResult' does not work in wpf. You have to use 'MessageBoxResult'.
– matsolof
Feb 1 '14 at 10:54
add a commen...
Add line break within tooltips
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if entity code 
 doesn't work, try 
 i am using linux and chrome not sure about other browsers
– Krishna
Nov 1 '16 at 9:20
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proper name for python * operator?
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Unfortunately INTERCAL does not have * as an operator so we're lacking for an official source...
– wberry
Jul 17 '13 at 23:33
4
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Tags for Emacs: Relationship between etags, ebrowse, cscope, GNU Global and exuberant ctags
...uages it currently supports) and closes the gap between IDEs and Emacs. It doesn't really interface with tools like etags and cscope, but it doesn't mean you cannot use them together.
Hopefully my explanations make sense and will be useful to you.
P.S. I'm not quite familiar with global and ebrow...