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Calling constructors in c++ without new
...d the most common way of creating new dynamic objects instead of using auto_ptr, unique_ptr, or related.
– Fred Nurk
Jan 18 '11 at 13:18
3
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What is the most accurate way to retrieve a user's correct IP address in PHP?
I know there are a plethora of $_SERVER variables headers available for IP address retrieval. I was wondering if there is a general consensus as to how to most accurately retrieve a user's real IP address (well knowing no method is perfect) using said variables?
...
How do I print the elements of a C++ vector in GDB?
...td::vector<int> called myVector, do the following:
print *(myVector._M_impl._M_start)@myVector.size()
To print only the first N elements, do:
print *(myVector._M_impl._M_start)@N
Explanation
This is probably heavily dependent on your compiler version, but for GCC 4.1.2, the pointer to t...
Open link in new tab or window [duplicate]
...
You should add the target="_blank" and rel="noopener noreferrer" in the anchor tag.
For example:
<a target="_blank" rel="noopener noreferrer" href="http://your_url_here.html">Link</a>
Adding rel="noopener noreferrer" is not mandatory, b...
Best practice for Django project working directory structure
...cts, but doesn't have to be. It usually looks like this:
~/projects/project_name/
docs/ # documentation
scripts/
manage.py # installed to PATH via setup.py
project_name/ # project dir (the one which django-admin.py creates)
apps/ # project-specific applic...
How to open a URL in a new Tab using JavaScript or jQuery? [duplicate]
...
Use window.open():
var win = window.open('http://stackoverflow.com/', '_blank');
if (win) {
//Browser has allowed it to be opened
win.focus();
} else {
//Browser has blocked it
alert('Please allow popups for this website');
}
Depending on the browsers implementation this will w...
How to check if a python module exists without importing it
...mport can find something in python2, using imp
import imp
try:
imp.find_module('eggs')
found = True
except ImportError:
found = False
To find dotted imports, you need to do more:
import imp
try:
spam_info = imp.find_module('spam')
spam = imp.load_module('spam', *spam_info)
i...
What is the proper way to comment functions in Python?
...odule, function, class, or method definition. Such a docstring becomes the __doc__ special attribute of that object.
All modules should normally have docstrings, and all functions and classes exported by a module should also have docstrings. Public methods (including the __init__ constructor) s...
Is it possible to declare two variables of different types in a for loop?
...:
auto [vec, i32] = std::tuple{std::vector<int>{3, 4, 5}, std::int32_t{12}}
A specific application of this is iterating over a map, getting the key and value,
std::unordered_map<K, V> m = { /*...*/ };
for (auto& [key, value] : m) {
// ...
}
See a live example here
C++14: ...
ARC and bridged cast
...ription is confusing. Since I just grasped them, I'll try to summarize:
(__bridge_transfer <NSType>) op or alternatively CFBridgingRelease(op) is used to consume a retain-count of a CFTypeRef while transferring it over to ARC. This could also be represented by id someObj = (__bridge <NSTy...