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How to understand nil vs. empty vs. blank in Ruby
...s the negation of .blank?.
Array gotcha: blank? will return false even if all elements of an array are blank. To determine blankness in this case, use all? with blank?, for example:
[ nil, '' ].blank? == false
[ nil, '' ].all? &:blank? == true
...
Get elements by attribute when querySelectorAll is not available without using libraries?
... and returns only those elements with a "data-foo" attribute:
function getAllElementsWithAttribute(attribute)
{
var matchingElements = [];
var allElements = document.getElementsByTagName('*');
for (var i = 0, n = allElements.length; i < n; i++)
{
if (allElements[i].getAttribute(attri...
Explain “claims-based authentication” to a 5-year-old
...n the ID is valid, and the ID is for the person requesting the drink. For all intents and purposes, the bartender (or application) doesn't really care how the authentication occurred because of the trust. The bartender knows nothing about you except your date of birth because that's all the barten...
addEventListener vs onclick
...se);
Using this approach (DOM Level 2 events), you can attach a theoretically unlimited number of events to any single element. The only practical limitation is client-side memory and other performance concerns, which are different for each browser.
The examples above represent using an anonymous...
C# Test if user has write access to a folder
I need to test if a user can write to a folder before actually attempting to do so.
18 Answers
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What is a daemon thread in Java?
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For posterity, setDamon(boolean) can only be called before the thread has been started. By default the thread inherits the daemon status of its parent thread.
– Gray
Nov 30 '11 at 13:47
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How do I design a class in Python?
I've had some really awesome help on my previous questions for detecting paws and toes within a paw , but all these solutions only work for one measurement at a time.
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How to create a new (and empty!) “root” branch?
...ository. By "root" branch I mean a branch that is entirely independent of all the other branches in the repository 1 .
4 A...
What happens to a detached thread when main() exits?
..._local) variables of other threads nor static objects.
This appears to be allowed to allow thread managers as static objects (note in [basic.start.term]/4 says as much, thanks to @dyp for the pointer).
Problems arise when the destruction of static objects has finished, because then execution enter...
Choosing between qplot() and ggplot() in ggplot2 [closed]
...I will use this
Of course, more complex plots require ggplot(), and I usually store data in data.frame, so in my experience, I rarely use qplot.
And it sounds good to always use ggplot(). While qplot saves typing, you lose a lot of functionalities.
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