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JavaScript closure inside loops – simple practical example
...pport let but get the above wrong (they don't create a new i each time, so all the functions above would log 3 like they would if we used var). Edge 14 finally gets it right.
ES5.1 solution: forEach
With the relatively widespread availability of the Array.prototype.forEach function (in 2015), it's ...
How to set java_home on Windows 7?
...
Find JDK Installation Directory
First you need to know the installation path for the Java Development Kit.
Open the default installation path for the JDK:
C:\Program Files\Java
There should be a subdirectory like:
C:\Program Files\J...
What is the difference between screenX/Y, clientX/Y and pageX/Y?
...upper left. This point could be anywhere in the browser window and can actually change location if there are embedded scrollable pages embedded within pages and the user moves a scrollbar.
screenX and screenY:
Relative to the top left of the physical screen/monitor, this reference point only moves ...
Split a string by a delimiter in python
...
@EndenDragon The for loop will automatically apply x.strip() and return a list of matches without whitespace on either side. The devil is in the details.
– Sébastien Vercammen
Jun 29 '16 at 13:59
...
How do I merge two dictionaries in a single expression in Python (taking union of dictionaries)?
...tionaries in a single expression?
For dictionaries x and y, z becomes a shallowly merged dictionary with values from y replacing those from x.
In Python 3.5 or greater:
z = {**x, **y}
In Python 2, (or 3.4 or lower) write a function:
def merge_two_dicts(x, y):
z = x.copy() # start with x's ...
Image Greyscale with CSS & re-color on mouse-over?
...rayscale(100%);
/* Chrome 19+ & Safari 6+ */
-webkit-transition: all .6s ease;
/* Fade to color for Chrome and Safari */
-webkit-backface-visibility: hidden;
/* Fix for transition flickering */
}
img.grayscale:hover {
filter: none;
-webkit-filter: grayscale(0%);
}
sv...
Android Center text on canvas
... at the center position: int xPos = (Width - textPaint.TextSize * Math.Abs(_text.Length / 2)) / 2; Not sure if there's a better way to accomplish this.
– paj7777
Apr 8 '13 at 9:06
...
Retrieve only the queried element in an object array in MongoDB collection
...r to filter an array during projection, which has the benefit of including all matches, instead of just the first one.
db.test.aggregate([
// Get just the docs that contain a shapes element where color is 'red'
{$match: {'shapes.color': 'red'}},
{$project: {
shapes: {$filter: {
...
How to define a two-dimensional array?
...
You're technically trying to index an uninitialized array. You have to first initialize the outer list with lists before adding items; Python calls this
"list comprehension".
# Creates a list containing 5 lists, each of 8 items, all set t...
Changing the cursor in WPF sometimes works, sometimes doesn't
...deCursor:
Mouse.OverrideCursor = Cursors.Wait;
try
{
// do stuff
}
finally
{
Mouse.OverrideCursor = null;
}
This overrides the cursor for your application rather than just for a part of its UI, so the problem you're describing goes away.
...