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How to check if element has any children in Javascript?
...
A couple of ways:
if (element.firstChild) {
// It has at least one
}
or the hasChildNodes() function:
if (element.hasChildNodes()) {
// It has at least one
}
or the length property of childNodes:
if (element.childNodes.length > 0) { // Or just `if (element.childNodes.length)...
How to define a two-dimensional array?
...array type with two dimensions. There are many ways to create a new array; one of the most useful is the zeros function, which takes a shape parameter and returns an array of the given shape, with the values initialized to zero:
>>> import numpy
>>> numpy.zeros((5, 5))
array([[ 0....
Use of 'use utf8;' gives me 'Wide character in print'
...;'
233:184:161:10
The first three bytes make up your character, the last one is the line-feed.
The call to print sends these four characters to STDOUT. Your console then works out how to display these characters. If your console is set to use UTF8, then it will interpret those three bytes as your...
How to implement Enums in Ruby?
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I'm surprised that no one has offered something like the following (harvested from the RAPI gem):
class Enum
private
def self.enum_attr(name, num)
name = name.to_s
define_method(name + '?') do
@attrs & num != 0
end
...
How to merge every two lines into one from the command line?
...tack as many of them as you want I expect.
– ThorSummoner
Dec 8 '16 at 0:12
1
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How do lexical closures work?
...environments for each of the functions created, with a different i in each one.
flist = []
for i in xrange(3):
def funcC(j):
def func(x): return x * j
return func
flist.append(funcC(i))
for f in flist:
print f(2)
This is what happens when you mix side effects and fun...
How can I make setuptools install a package that's not on PyPI?
...available from GitHub. The python-gearman version that's on PyPI is an old one. The Github source is setuptools-compatible, i.e. has setup.py, etc. Is there a way to make setuptools download and install the new version instead of looking for it on PyPI and installing the old one?
...
With Spring can I make an optional path variable?
...use the path can't be that complex while being filled up with optional components. If you have more than one or max two optional path elements you should seriously consider switching a few of them to request parameters.
– Patrick Cornelissen
Apr 23 '12 at 10:44...
MySQL: @variable vs. variable. What's the difference?
In another question I posted someone told me that there is a difference between:
4 Answers
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github markdown colspan
...itHub (but not on StackOverflow)
<table>
<tr>
<td>One</td>
<td>Two</td>
</tr>
<tr>
<td colspan="2">Three</td>
</tr>
</table>
Becomes
...