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Why is auto_ptr being deprecated?
... access to object is SEQUENTIAL, then go for unique_ptr.
By SEQUENTIAL, I mean, at any point object will be accessed from one context. E.g. a object that was created, and used immediately after creation by the creator. After creation the object is stored in FIRST data-structure. Then either the obj...
Why does Double.NaN==Double.NaN return false?
...
NaN means "Not a Number".
Java Language Specification (JLS) Third Edition says:
An operation that overflows produces a signed infinity, an operation that underflows produces a denormalized value or a signed zero, and an oper...
In Python, what is the difference between “.append()” and “+= []”?
...l add one item to the list, while += will copy all elements of right-hand-side list into the left-hand-side list.
Update: perf analysis
Comparing bytecodes we can assume that append version wastes cycles in LOAD_ATTR + CALL_FUNCTION, and += version -- in BUILD_LIST. Apparently BUILD_LIST outweighs...
How do I change the data type for a column in MySQL?
...ter table ... change ... method, for example:
mysql> create table yar (id int);
Query OK, 0 rows affected (0.01 sec)
mysql> insert into yar values(5);
Query OK, 1 row affected (0.01 sec)
mysql> alter table yar change id id varchar(255);
Query OK, 1 row affected (0.03 sec)
Records: 1 Dup...
Is it possible to send a variable number of arguments to a JavaScript function?
... as input. An arguments function typically is written like this:
function mean(){
let args = [...arguments];
return args.reduce((a,b)=>a+b) / args.length;
}
Sometimes, the function header is written like the following to document the arguments in a C-like fashion:
function mean(/* ......
What are the best practices for catching and re-throwing exceptions?
...You should not be catching the exception unless you intend to do something meaningful.
"Something meaningful" might be one of these:
Handling the exception
The most obvious meaningful action is to handle the exception, e.g. by displaying an error message and aborting the operation:
try {
$co...
Why did my Git repo enter a detached HEAD state?
...rking directory. Additionally, files are copied to the stage. What does it mean by "files are copied to the stage"? I thought the files are committed, which means the stage is cleared?
– max
Sep 3 '13 at 1:46
...
Monad in plain English? (For the OOP programmer with no FP background)
...n operations provided.
First, what is an "amplifier of types"? By that I mean some system which lets you take a type and turn it into a more special type. For example, in C# consider Nullable<T>. This is an amplifier of types. It lets you take a type, say int, and add a new capability to tha...
How do you serialize a model instance in Django?
...
This didn't work for me. Django throws AttributeError 'tuple' object has no attribute '_meta'
– adamF
Oct 28 '15 at 16:05
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What exactly is nullptr?
...ther it would be finished 2008 or 2009. Note that it actually became C++0B meaning C++11. See stroustrup.com/C++11FAQ.html
– mxmlnkn
Apr 14 '16 at 9:59
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