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What are POD types in C++?
...pod<MyType>() to tell whether MyType is POD.
– allyourcode
Mar 31 '14 at 21:24
7
Bjarne Str...
Find XOR of all numbers in a given range
... binary representation and then the decimal result and its relation to its index (a) into the XOR list. This happens because all the upper bits cancel and the lowest two bits cycle every 4. So, that's how to arrive at that little lookup table.
Now, consider for a general range of [a,b]. We can use...
Are there any standard exit status codes in Linux?
...ld died with 11" */
}
How are you determining the exit status? Traditionally, the shell only stores an 8-bit return code, but sets the high bit if the process was abnormally terminated.
$ sh -c 'exit 42'; echo $?
42
$ sh -c 'kill -SEGV $$'; echo $?
Segmentation fault
139
$ expr 139 - 128
11
I...
ASP.NET MVC: No parameterless constructor defined for this object
...same exception occurs when a Model has no parameterless constructor.
The call stack was figuring a method responsible for creating a new instance of a model.
System.Web.Mvc.DefaultModelBinder.CreateModel(ControllerContext controllerContext, ModelBindingContext bindingContext, Type modelType)
...
How to create a responsive image that also scales up in Bootstrap 3
...
Try to do so:
1) In your index.html
<div class="col-lg-3 col-md-4 col-xs-6 thumb">
<a class="thumbnail" href="#">
<div class="ratio" style="background-image:url('../Images/img1.jpg')"></div>
</a>
</div>
...
Auto reloading python Flask app upon code changes
...nt recommended way is with the flask command line utility.
https://flask.palletsprojects.com/en/1.1.x/quickstart/#debug-mode
Example:
$ export FLASK_APP=main.py
$ export FLASK_ENV=development
$ flask run
or in one command:
$ FLASK_APP=main.py FLASK_ENV=development flask run
If you want diff...
More elegant way of declaring multiple variables at the same time
...variables with Boolean values is the best way to write your routine (especially if they really have one-letter names :)
Depending on what you're doing, it may make sense to use a dictionary instead. For example, if you want to set up Boolean preset values for a set of one-letter flags, you could d...
What is the difference between #include and #include “filename”?
...unix archive), and used the string between the < and > as the key to index into the library.
– Adrian McCarthy
Feb 15 '17 at 23:14
|
s...
pytest: assert almost equal
...
I noticed that this question specifically asked about py.test. py.test 3.0 includes an approx() function (well, really class) that is very useful for this purpose.
import pytest
assert 2.2 == pytest.approx(2.3)
# fails, default is ± 2.3e-06
assert 2.2 == pyte...
How to install MySQLdb (Python data access library to MySQL) on Mac OS X?
...
Update for those using Python3:
You can simply use conda install mysqlclient to install the libraries required to use MySQLdb as it currently exists. The following SO question was a helpful clue: Python 3 ImportError: No module named 'ConfigParser' . Installing mysqlclient will install...