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How many String objects will be created when using a plus sign?
...catenating in a loop. E.g. How many string objects does the following code allocate: string s = ""; for (int i = 0; i < n; i++) s += "a";
– Joren
Feb 3 '12 at 20:08
1
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C# member variable initialization; best practice?
... If an exception is thrown in a field initializer, any resources that were allocated in previous initializers will be abandoned; there's no way to prevent it. Other errors in construction can be dealt with, if awkwardly, by having a protected base constructor accept an IDisposable by reference, and...
Does Ruby regular expression have a not match operator like “!~” in Perl?
... you can easily negate. According to the release notes, it does even fewer allocations than !~
– panmari
May 28 '18 at 20:52
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startsWith() and endsWith() functions in PHP
...s so far seem to do loads of unnecessary work, strlen calculations, string allocations (substr), etc. The 'strpos' and 'stripos' functions return the index of the first occurrence of $needle in $haystack:
function startsWith($haystack,$needle,$case=true)
{
if ($case)
return strpos($hays...
Enumerable.Empty() equivalent for IQueryable
...umerable.Empty<T>().AsQueryable();
are preferred. Array.Empty will allocate a static typed array so only one empty array of T is created and that is shared amongst all Empty queryables.
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Can we instantiate an abstract class?
...that here: -
Whenever a new class instance is created, memory space is allocated
for it with room for all the instance variables declared in the class
type and all the instance variables declared in each superclass of the
class type, including all the instance variables that may be hidden....
Why is string concatenation faster than array join?
...y overhead.
On the other hand ['abc', 'def'].join('') would usually just allocate memory to lay out the new string flat in memory. (Maybe this should be optimized)
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WKWebView not loading local files under iOS 8
...athComponent;
... then start it up like so:
_webServer = [[GCDWebServer alloc] init];
[_webServer addGETHandlerForBasePath:@"/" directoryPath:docRoot indexFilename:@"index.html" cacheAge:3600 allowRangeRequests:YES];
[_webServer startWithPort:port bonjourName:nil];
To stop it:
[_webServer stop...
Picking a random element from a set
...w array? docs.oracle.com/javase/7/docs/api/java/util/… "this method must allocate a new array even if this collection is backed by an array"
– anton1980
Nov 22 '14 at 3:19
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In STL maps, is it better to use map::insert than []?
...es") and are destroyed.
Which means extra time for:
1. One objects memory allocation
2. One extra constructor call
3. One extra destructor call
4. One objects memory deallocation
If your objects are large, constructors are typical, destructors do a lot of resource freeing, above points count even ...