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How to remove elements from a generic list while iterating over it?
...e(i));
Alternately, you can use the RemoveAll method with a predicate to test against:
safePendingList.RemoveAll(item => item.Value == someValue);
Here's a simplified example to demonstrate:
var list = new List<int>(Enumerable.Range(1, 10));
Console.WriteLine("Before:");
list.ForEach(...
How can I pass a member function where a free function is expected?
... char * argv[])
{
...
aClass a;
auto fp = std::bind(&aClass::test, a, _1, _2);
function1(fp);
return 0;
}
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Django dynamic model fields
...ill Hardy's talk at DjangoCon 2011 (watch it!) are nevertheless robust and tested in production (relevant source code).
First to implement this was Michael Hall.
Yes, this is magic, with these approaches you can achieve fully dynamic Django apps, models and fields with any relational database back...
What's faster, SELECT DISTINCT or GROUP BY in MySQL?
...cit, so you can get away with a slightly dumber optimizer.
When in doubt, test!
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Most efficient way to remove special characters from string
...s if you would use it on a large string.
Edit:
I made a quick performance test, running each function a million times with a 24 character string. These are the results:
Original function: 54.5 ms.
My suggested change: 47.1 ms.
Mine with setting StringBuilder capacity: 43.3 ms.
Regular expression: ...
Why is there a difference in checking null against a value in VB.NET and C#?
...e by an unfortunate belief that it is confusing to have different means of testing equality yield different results, and such confusion might be avoided by having the different forms of equality yield the same results whenever possible.
In reality, the fundamental cause of confusion is a misguided ...
Performance difference between IIf() and If
...de effects.
Code illustration:
Module Module1
Sub Main()
Dim test As Boolean = False
Dim result As String = IIf(test, Foo(), Bar())
End Sub
Public Function Foo() As String
Console.WriteLine("Foo!")
Return "Foo"
End Function
Public Function Bar(...
how to emulate “insert ignore” and “on duplicate key update” (sql merge) with postgresql?
...start transaction; create temporary table temporary_table as select * from test where false; copy temporary_table from 'data_file.csv'; lock table test; update test set data=temporary_table.data from temporary_table where test.id=temporary_table.id; insert into test select * from temporary_table whe...
Best way to work with transactions in MS SQL Server Management Studio
...nt that you can also (and should if what you are writing is complex) add a test variable to rollback if you are in test mode. Then you can execute the whole thing at once. Often I also add code to see the before and after results of various operations especially if it is a complex script.
Example ...
Enable access control on simple HTTP server
.../env python3
from http.server import HTTPServer, SimpleHTTPRequestHandler, test
import sys
class CORSRequestHandler (SimpleHTTPRequestHandler):
def end_headers (self):
self.send_header('Access-Control-Allow-Origin', '*')
SimpleHTTPRequestHandler.end_headers(self)
if __name__ ==...