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Is there any overhead to declaring a variable within a loop? (C++)
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Stack space for local variables is usually allocated in function scope. So no stack pointer adjustment happens inside the loop, just assigning 4 to var. Therefore these two snippets have the same overhead.
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Validate that end date is greater than start date with jQuery
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I had to modify it slightly to allow for blank end dates in my app, but this did the bulk. code if (value == 0) { return true; } else if (!/Invalid|NaN/... code
– Frank Luke
Jun 23 '11 at 14:48
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PHP Fatal error: Using $this when not in object context
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@Sarfraz No offense, but it is still wrong. You can call an instance method with ::. It is against E_STRICT, but it does work as long as the method body does not reference the instance scope, e.g. uses $this. Also, self::foo will not point to $this->foo. It references a clas...
Java Serializable Object to Byte Array
...Object);
out.flush();
byte[] yourBytes = bos.toByteArray();
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} finally {
try {
bos.close();
} catch (IOException ex) {
// ignore close exception
}
}
Create an object from a byte array:
ByteArrayInputStream bis = new ByteArrayInputStream(yourBytes);
ObjectInput in = null;
tr...
SQL select join: is it possible to prefix all columns as 'prefix.*'?
...e is to assign a dummy column to separate each new table. This works especially well if you're looping through a result set for a list of columns in a scripting language such as Python or PHP.
SELECT '' as table1_dummy, table1.*, '' as table2_dummy, table2.*, '' as table3_dummy, table3.* FROM table...
Getting the index of the returned max or min item using max()/min() on a list
... values = [3,6,1,5], and need the index of the smallest element, i.e. index_min = 2 in this case.
Avoid the solution with itemgetter() presented in the other answers, and use instead
index_min = min(range(len(values)), key=values.__getitem__)
because it doesn't require to import operator nor to ...
Finding the type of an object in C++
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dynamic_cast should do the trick
TYPE& dynamic_cast<TYPE&> (object);
TYPE* dynamic_cast<TYPE*> (object);
The dynamic_cast keyword casts a datum from one pointer or reference type to another, performing a runtime...
Task vs Thread differences [duplicate]
I'm new to parallel programming. There are two classes available in .NET: Task and Thread .
4 Answers
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Python naming conventions for modules
I have a module whose purpose is to define a class called "nib". (and a few related classes too.) How should I call the module itself? "nib"? "nibmodule"? Anything else?
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Get Enum from Description attribute [duplicate]
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value.ToString() is expensive, do not call it twice (.. if it matters)...
– nawfal
Jun 11 '13 at 1:26
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