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When is a C++ destructor called?
Basic Question: when does a program call a class' destructor method in C++? I have been told that it is called whenever an object goes out of scope or is subjected to a delete
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Django ModelForm: What is save(commit=False) used for?
Why would I ever use save(commit=False) instead of just creating a form object from the ModelForm subclass and running is_valid() to validate both the form and model?
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What is an “unwrapped value” in Swift?
I'm learning Swift for iOS 8 / OSX 10.10 by following this tutorial , and the term " unwrapped value " is used several times, as in this paragraph (under Objects and Class ):
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What is the purpose of setting a key in data.table?
...set a key (e.g. X[Y] ). As such, I wish to understand what a key does in order to properly set keys in my data tables.
2 ...
Static linking vs dynamic linking
Are there any compelling performance reasons to choose static linking over dynamic linking or vice versa in certain situations? I've heard or read the following, but I don't know enough on the subject to vouch for its veracity.
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Check if a file exists with wildcard in shell script [duplicate]
...timization that also relies on glob expansion, but avoids the use of ls:
for f in /path/to/your/files*; do
## Check if the glob gets expanded to existing files.
## If not, f here will be exactly the pattern above
## and the exists test will evaluate to false.
[ -e "$f" ] &&...
When should I use GC.SuppressFinalize()?
...essFinalize should only be called by a class that has a finalizer. It's informing the Garbage Collector (GC) that this object was cleaned up fully.
The recommended IDisposable pattern when you have a finalizer is:
public class MyClass : IDisposable
{
private bool disposed = false;
protect...
How can I avoid Java code in JSP files, using JSP 2?
...) and EL (Expression Language, those ${} things) way back in 2001.
The major disadvantages of scriptlets are:
Reusability: you can't reuse scriptlets.
Replaceability: you can't make scriptlets abstract.
OO-ability: you can't make use of inheritance/composition.
Debuggability: if scriptlet throws ...
Please enter a commit message to explain why this merge is necessary, especially if it merges an upd
I am using Git. I did a pull from a remote repo and got an error message:
8 Answers
8
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Why is list initialization (using curly braces) better than the alternatives?
...nteger cannot be converted to another integer that cannot hold its value. For example, char
to int is allowed, but not int to char.
A floating-point value cannot be converted to another floating-point type that cannot hold its
value. For example, float to double is allowed, but not double to float.
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