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Google Guava isNullOrEmpty for collections
...eyard."
We don't believe that "is null or empty" is a question you ever really want to be asking about a collection.
If a collection might be null, and null should be treated the same as empty, then get all that ambiguity out of the way up front, like this:
Set<Foo> foos = NaughtyClass.getF...
How to replace list item in best way
... once for the index. Your approach uses Contains first which needs to loop all items(in the worst case), then you're using IndexOf which needs to enumerate the items again .
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Does const mean thread-safe in C++11?
...:
[17.6.5.9/1]
This section specifies requirements that implementations shall meet to prevent data races (1.10). Every standard library function shall meet each requirement unless otherwise specified. Implementations may prevent data races in cases other than those specified below.
[17.6.5.9/3]
A C...
How to comment and uncomment blocks of code in the Office VBA Editor
...ndy - I can't believe I'd never found it before. A shortcut key would be really handy but unfortunately that doesn't seem to exist.
– Jamie Bull
Oct 17 '12 at 12:26
3
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Sqlite: CURRENT_TIMESTAMP is in GMT, not the timezone of the machine
...me is wanted (I, for example, store local time in one of my database since all I care is what time in the day is was and I don't keep track of where I was in term of time zones...), you can define the column as
"timestamp" TEXT DEFAULT (strftime('%Y-%m-%dT%H:%M','now', 'localtime'))
The %Y-%m-%d...
Using an integer as a key in an associative array in JavaScript
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@bobince: Internally, sure. However, logically, arrays have integer "keys".
– Lightness Races in Orbit
Nov 17 '12 at 22:53
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Who is listening on a given TCP port on Mac OS X?
...y version of macOS supports this:
sudo lsof -iTCP -sTCP:LISTEN -n -P
Personally I've end up with this simple function in my ~/.bash_profile:
listening() {
if [ $# -eq 0 ]; then
sudo lsof -iTCP -sTCP:LISTEN -n -P
elif [ $# -eq 1 ]; then
sudo lsof -iTCP -sTCP:LISTEN -n -P | gre...
Bootstrap: how do I change the width of the container?
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Theoretically, there are infinite combinations that match 1000px. An example: 12*65 + 11*20 = 1000 (there are only 11 gutters between columns).
– albertedevigo
Jun 14 '13 at 14:09
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Unpacking, extended unpacking and nested extended unpacking
...luating these "by hand," I'll suggest some simple substitution rules. Basically, you might find it easier to understand an expression if all the iterables are formatted in the same way.
For the purposes of unpacking only, the following substitutions are valid on the right side of the = (i.e. for rv...
Spring MVC: How to perform validation?
...out that: I saw it validates a class. Does the class have to be filled manually with the values from the user input, and then passed to the validator?
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