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best way to get the key of a key/value javascript object
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You can now use spread operator for this purpose, it looks better: const [firstKey, ...rest] = Object.keys(obj);
– Nerlin
Dec 13 '17 at 21:08
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What exactly are DLL files, and how do they work?
...ly do DLL files work? There seems to be an awful lot of them, but I don't know what they are or how they work.
9 Answers
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jQuery AJAX cross domain
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It's 2016. CORS is now a widely supported standard, as opposed to JSONP which can only be described as a hack. @joshuarh's answer below should be the preferred one now.
– Vicky Chijwani
Jul 20 '16 at 9:16
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Why exactly is eval evil?
I know that Lisp and Scheme programmers usually say that eval should be avoided unless strictly necessary. I’ve seen the same recommendation for several programming languages, but I’ve not yet seen a list of clear arguments against the use of eval . Where can I find an account of the potentia...
Gridview with two columns and auto resized images
...white"
android:background="#55000000"/>
</FrameLayout>
Now make some sort of adapter for your GridView:
src/com/example/graphicstest/MyAdapter.java
private final class MyAdapter extends BaseAdapter {
private final List<Item> mItems = new ArrayList<Item>();
p...
Multiple constructors in python? [duplicate]
...d
def fromfilename(cls, name):
return cls(open(name, 'rb'))
# Now you can do:
c = C(fd)
# or:
c = C.fromfilename('a filename')
Notice all those classmethods still go through the same __init__, but using classmethods can be much more convenient than having to remember what combinations...
How do I create a namespace package in Python?
...introduces implicit namespace packages, see PEP 420.
This means there are now three types of object that can be created by an import foo:
A module represented by a foo.py file
A regular package, represented by a directory foo containing an __init__.py file
A namespace package, represented by one ...
When to use AtomicReference in Java?
...or the java.util.concurrent framework rather than bare Atomic* unless you know what you're doing.
Two excellent dead-tree references which will introduce you to this topic:
Herlihy's excellent Art of Multiprocessor Programming
Java Concurrency in Practice
Note that (I don't know if this has ...
Redirect stderr and stdout in Bash
... 2>&1
echo "This line will appear in $LOG_FILE, not 'on screen'"
Now, simple echo will write to $LOG_FILE. Useful for daemonizing.
To the author of the original post,
It depends what you need to achieve. If you just need to redirect in/out of a command you call from your script, the answ...
How to check if an appSettings key exists?
...ager.AppSettings
if (ConfigurationManager.AppSettings[name] != null)
{
// Now do your magic..
}
or
string s = ConfigurationManager.AppSettings["myKey"];
if (!String.IsNullOrEmpty(s))
{
// Key exists
}
else
{
// Key doesn't exist
}
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