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When saving, how can you check if a field has changed?
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Essentially, you want to override the __init__ method of models.Model so that you keep a copy of the original value. This makes it so that you don't have to do another DB lookup (which is always a good thing).
class Person(models.Model):
name = models.CharField...
Facebook Callback appends '#_=_' to Return URL
...p; history.pushState) {
window.history.pushState("", document.title, window.location.pathname);
} else {
// Prevent scrolling by storing the page's current scroll offset
var scroll = {
top: document.body.scrollTop,
left: doc...
capturing self strongly in this block is likely to lead to a retain cycle
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The capture of self here is coming in with your implicit property access of self.timerDisp - you can't refer to self or properties on self from within a block that will be strongly retained by self.
You can get around this by creating a weak reference to self bef...
How to convert JSON data into a Python object
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UPDATE
With Python3, you can do it in one line, using SimpleNamespace and object_hook:
import json
from types import SimpleNamespace
data = '{"name": "John Smith", "hometown": {"name": "New York", "id": 123}}'
# Parse JSON into an ...
SQL Server Insert if not exists
... Assunto = @_ASSUNTO
AND Data = @_DATA);
END
replace with
BEGIN
IF NOT EXISTS (SELECT * FROM EmailsRecebidos
WHERE De = @_DE
AND Assunto = @_ASSUNTO
AND Data = @_DATA)
BEGIN
INSERT INTO EmailsRecebidos (De,...
“Notice: Undefined variable”, “Notice: Undefined index”, and “Notice: Undefined offset” using PHP
... vast wisdom of the PHP Manual:
Relying on the default value of an uninitialized variable is problematic in the case of including one file into another which uses the same variable name. It is also a major security risk with register_globals turned on. E_NOTICE level error is issued in case of w...
How to capture stdout output from a Python function call?
... sys.stdout = self._stringio = StringIO()
return self
def __exit__(self, *args):
self.extend(self._stringio.getvalue().splitlines())
del self._stringio # free up some memory
sys.stdout = self._stdout
Usage:
with Capturing() as output:
do_something(my_ob...
(Mac) -bash: __git_ps1: command not found
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You've installed the version of git-completion.bash from master - in git's development history this is after a commit that split out the __git_ps1 function from the completion functionality into a new file (git-prompt.sh). The commit that introduced this ch...
Two way/reverse map [duplicate]
I'm doing this switchboard thing in python where I need to keep track of who's talking to whom, so if Alice --> Bob, then that implies that Bob --> Alice.
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Return positions of a regex match() in Javascript?
Is there a way to retrieve the (starting) character positions inside a string of the results of a regex match() in Javascript?
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