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DateTime “null” value
I've been searching a lot but couldn't find a solution. How do you deal with a DateTime that should be able to contain an uninitialized value (equivalent to null)? I have a class which might have a DateTime property value set or not. I was thinking of initializing the property holder to DateTime.Min...
What does default(object); do in C#?
...s a zero-initialized value
For Nullable<T> it returns the empty (pseudo-null) value (actually, this is a re-statement of the first bullet, but it is worth making it explicit)
The biggest use of default(T) is in generics, and things like the Try... pattern:
bool TryGetValue(out T value) {
...
Getting SyntaxError for print with keyword argument end=' '
... to print with a tuple as argument.
That's obviously bad syntax (literals don't take keyword arguments). In Python 3.x print is an actual function, so it takes keyword arguments, too.
The correct idiom in Python 2.x for end=" " is:
print "foo" % bar,
(note the final comma, this makes it end the...
In Bash, how can I check if a string begins with some value?
...ing Guide says:
# The == comparison operator behaves differently within a double-brackets
# test than within single brackets.
[[ $a == z* ]] # True if $a starts with a "z" (wildcard matching).
[[ $a == "z*" ]] # True if $a is equal to z* (literal matching).
So you had it nearly correct; you ne...
From inside of a Docker container, how do I connect to the localhost of the machine?
So I have a Nginx running inside a docker container, I have a mysql running on localhost, I want to connect to the MySql from within my Nginx. The MySql is running on localhost and not exposing a port to the outside world, so its bound on localhost, not bound on the ip address of the machine.
...
How do you write tests for the argparse portion of a python module? [closed]
I have a Python module that uses the argparse library. How do I write tests for that section of the code base?
9 Answers
...
Vim delete blank lines
...This is my favorite answer, since it actually explains what the :g command does.
– Tim Swast
Aug 15 '11 at 19:03
4
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Can you use @Autowired with static fields?
... use @Autowired with static fields. If not, are there some other ways to do this?
10 Answers
...
How do you stretch an image to fill a while keeping the image's aspect-ratio?
...
Update 2016:
Modern browser behave much better. All you should need to do is to set the image width to 100% (demo)
.container img {
width: 100%;
}
Since you don't know the aspect ratio, you'll have to use some scripting. Here is how I would do it with jQuery (demo):
CSS
.container {
...
How do I add tab completion to the Python shell?
...
I may have found a way to do it.
Create a file .pythonrc
# ~/.pythonrc
# enable syntax completion
try:
import readline
except ImportError:
print("Module readline not available.")
else:
import rlcompleter
readline.parse_and_bind("tab:...