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Is it better to return null or empty collection?
... or "don't know". We could throw an exception, but it's not necessarily an error condition, and it doesn't necessarily drive us out of the normal program flow.
I've often been frustrated by systems that cannot distinguish between zero and no answer. I've had a number of times where a system has ask...
Initialize a long in Java
...ormed.
Try this
byte a = 1; // declare a byte
a = a*2; // you will get error here
You get error because 2 is by default int.
Hence you are trying to multiply byte with int.
Hence result gets typecasted to int which can't be assigned back to byte.
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MySQL date format DD/MM/YYYY select query?
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John CondeJohn Conde
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Python: finding an element in a list [duplicate]
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But this code gives error when element is not in the list.In current example context if I search for 'three' (i.e: li.index('three')) gives error.
– Kedar.Aitawdekar
May 28 '14 at 7:31
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How to parse JSON in Scala using standard Scala classes?
...answer, it led me down the right path. However, it isn't great at handling error conditions. If the desired node does not exist, you get a cast exception. I've adapted this slightly to make use of Option to better handle this.
class CC[T] {
def unapply(a:Option[Any]):Option[T] = if (a.isEmpty) {
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Python: Making a beep noise
...'re using Python 3, don't forget to use parentheses or you'll get a syntax error. Use print('\a')
– ZorroDeLaArena
Mar 27 '15 at 19:38
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sho...
Postgis installation: type “geometry” does not exist
...I do it by this page . But when I import postgis.sql file, I get a lot of errors:
10 Answers
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Create a pointer to two-dimensional array
...e is how they do
uint8_t (*matrix_ptr)[][20] = l_matrix;
If you fix the error and add the address-of operator & like in the following snippet
uint8_t (*matrix_ptr)[][20] = &l_matrix;
Then that one creates a pointer to an incomplete array type of elements of type array of 20 uint8_t. Be...
Why does intellisense and code suggestion stop working when Visual Studio is open?
...date from this, either.
Copy/pasting code from another page that caused an error because the code copied referred to a control that wasn't on the page I was pasting to.
C++ project has corrupt .ncb file
(Please add to comments if you notice behavior that causes this.)
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Setting variable to NULL after free
...ou get an immediate crash on most systems, telling you right away what the error is.
For local variables, it may be a little bit pointless if it is "obvious" that the pointer isn't accessed anymore after being freed, so this style is more appropriate for member data and global variables. Even for l...