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Captured variable in a loop in C#
...ompiler is generating a class that represents the closure for your method call. It uses that single instance of the closure class for each iteration of the loop. The code looks something like this, which makes it easier to see why the bug happens:
void Main()
{
List<Func<int>> actio...
How do I count the number of occurrences of a char in a String?
...
The loop method is much faster than this. Especially when wanting to count a char instead of a String (since there is no String.replace(char, char) method). On a 15 character string, I get a difference of 6049 ns vs 26,739 ns (averaged over 100runs). Raw numbers are huge...
Where IN clause in LINQ [duplicate]
... source, params T[] list)
{
return list.Contains(source);
}
Now you call:
var states = _objdatasources.StateList().Where(s => s.In(countrycodes));
You can pass individual values too:
var states = tooManyStates.Where(s => s.In("x", "y", "z"));
Feels more natural and closer to sql.
...
How to programmatically show next view in ViewPager?
...sed it
– Tomas Wolf
Oct 9 '14 at 16:32
2
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How do I create a copy of an object in PHP?
...ass by reference is a bad idea, because it makes the effect of a function call depend on the implementation of the function, rather than on the specification. It's got nothing to do with pass by value being the default.
– Oswald
Oct 4 '13 at 7:06
...
How to drop all tables in a SQL Server database?
...y tables.
I found that code that works and does everything you try (delete all tables from your database):
DECLARE @Sql NVARCHAR(500) DECLARE @Cursor CURSOR
SET @Cursor = CURSOR FAST_FORWARD FOR
SELECT DISTINCT sql = 'ALTER TABLE [' + tc2.TABLE_SCHEMA + '].[' + tc2.TABLE_NAME + '] DROP [' + rc1.C...
Python: What OS am I running on?
...consistent output. i.e. platform.system() returns "Windows" instead of "win32". sys.platform also contains "linux2" on old versions of Python while it contains just "linux" on newer ones. platform.system() has always returned just "Linux".
– erb
Jun 9 '17 at 10...
How do I find all files containing specific text on Linux?
I'm trying to find a way to scan my entire Linux system for all files containing a specific string of text. Just to clarify, I'm looking for text within the file, not in the file name.
...
How efficient is locking an unlocked mutex? What is the cost of a mutex?
... access to the object happens often, then multiple locks would increase parallelism. At the cost of maintainability, since more locking means more debugging of the locking.
How efficient is it to lock a mutex? I.e. how much assembler instructions are there likely and how much time do they take (...
Unique BooleanField value in Django?
... save method of the model and if you've set the boolean to True, make sure all others are set to False.
from django.db import transaction
class Character(models.Model):
name = models.CharField(max_length=255)
is_the_chosen_one = models.BooleanField()
def save(self, *args, **kwargs):
...