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When should I use the new keyword in C++?
...
Method 1 (using new)
Allocates memory for the object on the free store (This is frequently the same thing as the heap)
Requires you to explicitly delete your object later. (If you don't delete it, you could create a memory leak)
Memory stays al...
How to repeat a string a variable number of times in C++?
...ster implementation, the idea is to minimise copying operations and memory allocations by first exponentially growing the string:
#include <string>
#include <cstddef>
std::string repeat(std::string str, const std::size_t n)
{
if (n == 0) {
str.clear();
str.shrink_to...
What is the difference between CMD and ENTRYPOINT in a Dockerfile?
...3 packets received, 0% packet loss
round-trip min/avg/max/stddev = 0.088/0.091/0.096/0.000 ms
Now, running the image with an argument will ping the argument:
$ docker run -it test google.com
PING google.com (173.194.45.70): 48 data bytes
56 bytes from 173.194.45.70: icmp_seq=0 ttl=55 time=32.583 ...
How does Stack Overflow generate its SEO-friendly URLs?
... string. That is, we never want “my-slug-”. This means an extra string allocation to remove it on this edge case. I’ve worked around this by delay-hyphening. If you compare my code to Jeff’s the logic for this is easy to follow.
His approach is purely lookup based and missed a lot of charact...
C++ new int[0] — will it allocate memory?
... When the value of the expression in a direct-new-declarator is zero, the allocation function is called to allocate an array with no elements.
From 3.7.3.1/2
The effect of dereferencing a pointer returned as a request for zero size is undefined.
Also
Even if the size of the space reques...
Do threads have a distinct heap?
... a stack overflow.
Since all threads share the same heap, access to the allocator/deallocator must be synchronized. There are various methods and libraries for avoiding allocator contention.
Some languages allow you to create private pools of memory, or individual heaps, which you can assign ...
What column type/length should I use for storing a Bcrypt hashed password in a Database?
... gold plate. If the software that you are using requires sixty bytes, then allocate sixty bytes. If there is a future release to your software that changes this, then you can worry about it when that release happens. You shouldn't be automatically installing functionality-changing updates.
...
Use of alloc init instead of new
...ere are a bunch of reasons here: http://macresearch.org/difference-between-alloc-init-and-new
Some selected ones are:
new doesn't support custom initializers (like initWithString)
alloc-init is more explicit than new
General opinion seems to be that you should use whatever you're comfortable wi...
Invalid argument supplied for foreach()
...ue)
{
...
}
}
The reason for my preference is it doesn't allocate an empty array when you've got nothing to begin with anyway.
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Difference between 'new operator' and 'operator new'?
...er, but it's a good question in any case.
Operator new is a function that allocates raw memory -- at least conceptually, it's not much different from malloc(). Though it's fairly unusual unless you're writing something like your own container, you can call operator new directly, like:
char *x = st...