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TransactionManagementError “You can't execute queries until the end of the 'atomic' block” while usi
...ementError when trying to save a Django User model instance and in its post_save signal, I'm saving some models that have the user as the foreign key.
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PHP and Enumerations
...
Depending upon use case, I would normally use something simple like the following:
abstract class DaysOfWeek
{
const Sunday = 0;
const Monday = 1;
// etc.
}
$today = DaysOfWeek::Sunday;
However, other use cases may require more validation of cons...
Set focus on TextBox in WPF from view model
...ample? Is it a TextBox control? If yes, then you are on a wrong way. Generally speaking it's not a good idea to have any reference to UI in your ViewModel. You can ask "Why?" but this is another question to post on Stackoverflow :).
The best way to track down issues with Focus is... debugging .Net ...
Python set to list
...k that you didn't overwrite list by accident:
>>> assert list == __builtins__.list
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Why is a round-trip conversion via a string not safe for a double?
...ber(value, 17, &number);
DoubleToNumber is pretty simple -- it just calls _ecvt, which is in the C runtime:
void DoubleToNumber(double value, int precision, NUMBER* number)
{
WRAPPER_CONTRACT
_ASSERTE(number != NULL);
number->precision = precision;
if (((FPDOUBLE*)&val...
How do I resolve configuration errors with Nant 0.91?
...xtracted from the Nant 0.91 archive. (This made no sense to me until I actually tried it, but it does actually work...)
Source : http://surfjungle.blogspot.com/2011/11/tip-running-nant-091-on-windows-7.html
I found that the problem was Windows 7 security related in that the downloaded NAnt 0.91...
this.setState isn't merging states as I would expect
...construct a new state and then call setState() on that:
var newSelected = _.extend({}, this.state.selected);
newSelected.name = 'Barfoo';
this.setState({ selected: newSelected });
I've used function _.extend() function (from underscore.js library) here to prevent modification to the existing sele...
NPM cannot install dependencies - Attempt to unlock something which hasn't been locked
I've been trying to run an npm install on my package.json file, but I'm having a lot of trouble. It keeps saying "Error: Attempt to unlock XXX, which hasn't been locked" on all my dependences. Here's one of them:
...
How can I get last characters of a string
...tring method .substr() combined with the .length property.
var id = "ctl03_Tabs1";
var lastFive = id.substr(id.length - 5); // => "Tabs1"
var lastChar = id.substr(id.length - 1); // => "1"
This gets the characters starting at id.length - 5 and, since the second argument for .substr() is omi...
Check if table exists and if it doesn't exist, create it in SQL Server 2008
...read, and you don't have to worry about sys.objects vs. sysobjects vs. sys.all_objects
vs. sys.tables. Basic form:
IF object_id('MyTable') is not null
PRINT 'Present!'
ELSE
PRINT 'Not accounted for'
Of course this will show as "Present" if there is any object present with that name. If yo...