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Does Java casting introduce overhead? Why?
...casting, when you cast from a type to a wider type, which is done automatically and there is no overhead:
String s = "Cast";
Object o = s; // implicit casting
Explicit casting, when you go from a wider type to a more narrow one. For this case, you must explicitly use casting like that:
Object o ...
Is there a reason that Swift array assignment is inconsistent (neither a reference nor a deep copy)?
...ead at some of the design decisions of the language. But the thing that really got me puzzled is how arrays are handled.
1...
Why does this (null || !TryParse) conditional result in “use of unassigned local variable”?
... illegal; if you replace dynamic with bool it compiles just fine.
I'm actually meeting with the C# team tomorrow; I'll mention it to them. Apologies for the error!
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What is a daemon thread in Java?
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For posterity, setDamon(boolean) can only be called before the thread has been started. By default the thread inherits the daemon status of its parent thread.
– Gray
Nov 30 '11 at 13:47
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Proper way to implement IXmlSerializable?
...ation that
was written by the WriteXml method.
When this method is called, the reader
is positioned at the start of the
element that wraps the information for
your type. That is, just before the
start tag that indicates the beginning
of a serialized object. When this
method return...
C compile error: “Variable-sized object may not be initialized”
...
I am assuming that you are using a C99 compiler (with support for dynamically sized arrays). The problem in your code is that at the time when the compilers sees your variable declaration it cannot know how many elements there are in the array (I am also assuming here, from the compiler error that...
What is the difference between an expression and a statement in Python?
...s, where operators include arithmetic and boolean operators, the function call operator () the subscription operator [] and similar, and can be reduced to some kind of "value", which can be any Python object. Examples:
3 + 5
map(lambda x: x*x, range(10))
[a.x for a in some_iterable]
yield 7
Stat...
Is it safe to delete a NULL pointer?
...ter delete. Setting a pointer to NULL after deleting it masquerades memory allocation errors, which is a very bad thing. A program that is correct does not delete a pointer twice, and a program that does delete a pointer twice should crash.
– Damon
Aug 30 '13 a...
How to convert a data frame column to numeric type?
... and this is not the most confounding thing, but it can confuse you, especially if you read this before rolling into bed.
Here goes: first two columns are character. I've deliberately called 2nd one fake_char. Spot the similarity of this character variable with one that Dirk created in his reply. I...
What is the maximum amount of RAM an app can use?
...he heap limit. And, since Android 3.0, apps can request a "large heap", usually in the hundreds of MB range, but that's considered poor form for most apps.
Furthermore, I noticed that some apps of mine crash with an OutOfMemoryException when using around 30-40 Megabytes.
Bear in mind that the ...