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Is if(items != null) superfluous before foreach(T item in items)?
...can matter. For most code we should choose the idiomatic code. But the two allocations you mentioned will be a performance problem in even fewer cases.
– CodesInChaos
Jun 23 '11 at 15:22
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in a “using” block is a SqlConnection closed on return or exception?
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Using generates a try / finally around the object being allocated and calls Dispose() for you.
It saves you the hassle of manually creating the try / finally block and calling Dispose()
share
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How do I count the number of occurrences of a char in a String?
...rs are huge difference, but percetage wise...it adds up. Avoid the memory allocations - use a loop!
– Ben
Nov 18 '14 at 15:41
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show 12 mor...
What is the difference between square brackets and parentheses in a regex?
...uestion uses keyword var in code, this probably is JavaScript). The use of php which runs on PCRE for preg matching will optimize away the lack of backtracking, however we're not in PHP either, so using classes [] instead of alternations | gives performance bonus as the match does not backtrack, and...
HTML character decoding in Objective-C / Cocoa Touch
...};
NSAttributedString *decodedString;
decodedString = [[NSAttributedString alloc] initWithData:stringData
options:options
documentAttributes:NULL
error:NULL];
T...
Is this a “good enough” random algorithm; why isn't it used if it's faster?
...have distinctly un-uniform output.
Inspired by this article about how bad php's rand() function is, I made some random matrix images using QuickRandom and System.Random. This run shows how sometimes the seed can have a bad effect (in this case favouring lower numbers) where as System.Random is pret...
How to set default values in Rails?
... method. That blog post's discussion about ActiveRecord directly calling .allocate was about model objects loaded with existing data from the database. (And it's a terrible idea for ActiveRecord to work that way, IMO. But that's beside the point.)
– SFEley
M...
What do all of Scala's symbolic operators mean?
...;: >: <% // Upper, lower and view bounds
<? <! // Start token for various XML elements
" """ // Strings
' // Indicate symbols and characters
@ // Annotations and variable binding on pattern matching
` // Denote constant or enable arbitrary identifie...
How do I increase the scrollback buffer in a running screen session?
...nificant hiccup. The higher the value you set, the more virtual memory is allocated to the screen process when initiating the screen session. I set my ~/.screenrc to "defscrollback 123456789" and when I initiated a screen, my entire system froze up for a good 10 minutes before coming back to the p...
How to dismiss keyboard for UITextView with return key?
...ad{
....
UITapGestureRecognizer *tapRec = [[UITapGestureRecognizer alloc]
initWithTarget:self action:@selector(tap:)];
[self.view addGestureRecognizer: tapRec];
....
}
-(void)tap:(UITapGestureRecognizer *)tapRec{
[[self view] endEditing: YES];
}
When the user taps out...