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Why is there no SortedList in Java?
In Java there are the SortedSet and SortedMap interfaces. Both belong to the Java Collections framework and provide a sorted way to access the elements.
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Django - Difference between import django.conf.settings and import settings
...ings file. django.conf.settings abstracts the concepts of default settings and site-specific settings; it presents a single interface. It also decouples the code that uses settings from the location of your settings.
UPDATE: if you want to define some own settings, see this part of the documentati...
Enter “&” symbol into a text Label in Windows Forms?
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Two ways:
Escape it with another ampersand (&&).
Set UseMnemonic for that label to false. This causes all ampersands within the text to be taken literally so you don't need to double any of them. You'll lose the underlining and access key features though.
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if a ngSrc path resolves to a 404, is there a way to fallback to a default?
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It's a pretty simple directive to watch for an error loading an image and to replace the src. (Plunker)
Html:
<img ng-src="smiley.png" err-src="http://google.com/favicon.ico" />
Javascript:
var app = angular.module("MyApp", []);
app.directive('errSrc', function() {
return {
l...
Combining INSERT INTO and WITH/CTE
I have a very complex CTE and I would like to insert the result into a physical table.
3 Answers
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What is the JavaScript version of sleep()?
...esolve or reject).
Compatibility
promises are supported in Node v0.12+ and widely supported in browsers, except IE
async/await landed in V8 and has been enabled by default since Chrome 55 (released in Dec 2016)
it landed in Node 7 in October 2016
and also landed in Firefox Nightly in November ...
What is the proper way to check for null values?
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.ToStringOrDefault() is simple and elegent. A nice solution.
– Chev
Mar 20 '12 at 14:16
7
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COUNT DISTINCT with CONDITIONS
... only positive values. Zeros or negative values would be evaluated as null and won't be included in count.
One thing to note here is that this can be done by reading the table once. When it seems that you have to read the same table twice or more, it can actually be done by reading once, in most of...
Why can't decimal numbers be represented exactly in binary?
...e the == operator to compare it to another floating-point number. I understand the principles behind floating-point representation.
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Java executors: how to be notified, without blocking, when a task completes?
... of the task.
You could even write a general wrapper for Runnable tasks, and submit these to ExecutorService. Or, see below for a mechanism built into Java 8.
class CallbackTask implements Runnable {
private final Runnable task;
private final Callback callback;
CallbackTask(Runnable task...