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Unique fields that allow nulls in Django
...pty string by providing your own customized model form for Foo with a clean_bar method that turns the empty string into None:
class FooForm(forms.ModelForm):
class Meta:
model = Foo
def clean_bar(self):
return self.cleaned_data['bar'] or None
class FooAdmin(admin.ModelAdmin...
Substitute multiple whitespace with single whitespace in Python [duplicate]
...ce characters that are combined.
To match unicode whitespace:
import re
_RE_COMBINE_WHITESPACE = re.compile(r"\s+")
my_str = _RE_COMBINE_WHITESPACE.sub(" ", my_str).strip()
To match ASCII whitespace only:
import re
_RE_COMBINE_WHITESPACE = re.compile(r"(?a:\s+)")
_RE_STRIP_WHITESPACE = re.co...
When to use reinterpret_cast?
...time hence the word static . This is the cast the C++ compiler uses internally for implicit casts also.
11 Answers
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How to remove a TFS Workspace Mapping?
...stating "Show Remote Workspaces" - just tick that and you'll get a list of all your enlistments:
From the command line
Call "tf workspace" from a developer command prompt. It will bring up the "Manage Workspaces" directly!
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MySQL: determine which database is selected?
After calling mysql_select_db to grab a database, is there any way to later output the name of the database that is currently selected? This seems very basic but I couldn't find anything on php.net or stackoverflow (all results are for "no database selected").
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Why can't I forward-declare a class in a namespace using double colons?
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All other answers were confusing to me but this "you can't declare a class within a namespace from outside that namespace. You have to be in the namespace." was very helpful hint to remember.
– dashesy
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Is there a limit to the length of a GET request? [duplicate]
...ns on request-target length are found in practice. It is RECOMMENDED that all HTTP senders and recipients support request-target lengths of 8000 or more octets." tools.ietf.org/html/…
– Mark Nottingham
Nov 16 '11 at 2:04
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django : using select_related and get_object_or_404 together
Is there any way of using get_object_or_404 and select_related together or any other way to achieve the result of using these two together(except from putting it in try/except)??
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How do you test running time of VBA code?
...Counter. Google it for more info. Try pushing the following into a class, call it CTimer say, then you can make an instance somewhere global and just call .StartCounter and .TimeElapsed
Option Explicit
Private Type LARGE_INTEGER
lowpart As Long
highpart As Long
End Type
Private Declare Fu...
Extract subset of key-value pairs from Python dictionary object?
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If you're using Python 3, and you only want keys in the new dict that actually exist in the original one, you can use the fact to view objects implement some set operations:
{k: bigdict[k] for k in bigdict.keys() & {'l', 'm', 'n'}}
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