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If my interface must return Task what is the best way to have a no-operation implementation?
...mprove performance even more if you cache the already completed task since all instances of completed tasks are the same:
public static class TaskExtensions
{
public static readonly Task CompletedTask = Task.FromResult(false);
}
With TaskExtensions.CompletedTask you can use the same instance ...
What does “export” do in shell programming? [duplicate]
... '^variable='
$ # No environment variable called variable
$ variable=Hello # Create local (non-exported) variable with value
$ env | grep '^variable='
$ # Still no environment variable called variable
$ export variable ...
Adding gif image in an ImageView in android
...imationActivity: -
public class AnimationActivity extends Activity {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
InputStream stream = null;
try {
stream = getAssets().open("pig...
Regular vs Context Free Grammars
...ammar is either right or left linear, whereas context free grammar is basically any combination of terminals and non-terminals. Hence you can see that regular grammar is a subset of context-free grammar.
So for a palindrome for instance, is of the form,
S->ABA
A->something
B->something
...
Difference between author and committer in Git?
...ld find was using the environment variables to override the committer:
GIT_COMMITTER_NAME='a' GIT_COMMITTER_EMAIL='a' git commit --author 'a <a>'
How to get the committer and commit date of a given commit?
Only author data shows by default on git log.
To see the committer date you can eit...
JavaScript variable number of arguments to function
Is there a way to allow "unlimited" vars for a function in JavaScript?
11 Answers
11
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Named colors in matplotlib
... have been moved under the 'xkcd:' prefix since I posted this answer originally.
I really didn't change much from the matplotlib example, but here is the code for completeness.
import matplotlib.pyplot as plt
from matplotlib import colors as mcolors
colors = dict(mcolors.BASE_COLORS, **mcolors...
Swift make method parameter mutable?
...eclare an inout parameter. Think: passing in a pointer.
func reduceToZero(_ x: inout Int) {
while (x != 0) {
x = x-1
}
}
var a = 3
reduceToZero(&a)
print(a) // will print '0'
This can be particularly useful in recursion.
Apple's inout declaration guidelines can be found...
How to convert a string into double and vice versa?
... Double is a numeric data type - it does not contain any formatting. Calling [NSString doubleValue] would return 1000 because it's just a number.
– Andy
Oct 5 '08 at 12:53
12
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Unable to open project… cannot be opened because the project file cannot be parsed
...
this should be marked as the answer. Really good stuff, thanks
– owen gerig
May 10 '13 at 15:10
12
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