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Replace a value if null or undefined in JavaScript
... boolean value but the first value that can be converted to true.
Additionally use an array of objects instead of one single object:
var options = {
filters: [
{
name: 'firstName',
value: 'abc'
}
]
};
var filter = options.filters[0] || ''; // is {n...
What does java:comp/env/ do?
...work.jndi.JndiObjectFactoryBean">
<property name="jndiName" value="foo"/>
</bean>
Then you can access it directly using:
Context ctx = new InitialContext();
DataSource ds = (DataSource)ctx.lookup("java:comp/env/foo");
or you could make an intermediate step so you don't have to ...
How to do a PUT request with curl?
...
"man curl" on -X: "Normally you don't need this option. All sorts of GET, HEAD, POST and PUT requests are rather invoked by using dedicated command line options." But I couldn't find another way.
– Martin C. Martin
...
When to choose checked and unchecked exceptions
...eople misunderstand what this means.
Predictable but unpreventable: The caller did everything within their power to validate the input parameters, but some condition outside their control has caused the operation to fail. For example, you try reading a file but someone deletes it between the time ...
insert multiple rows via a php array into mysql
...like you might be running into string-handling problems in PHP, which is really an algorithm problem, not a language one. Basically, when working with large strings, you want to minimize unnecessary copying. Primarily, this means you want to avoid concatenation. The fastest and most memory efficient...
How to remove duplicate white spaces in string using Java?
...
Like this:
yourString = yourString.replaceAll("\\s+", " ");
For example
System.out.println("lorem ipsum dolor \n sit.".replaceAll("\\s+", " "));
outputs
lorem ipsum dolor sit.
What does that \s+ mean?
\s+ is a regular expression. \s matches a space, tab...
Python: Append item to list N times
...a good idea for constant values, like ints or strings, is because only a shallow copy is does when using the <list>*<number> syntax, and thus if you did something like [{}]*100, you'd end up with 100 references to the same dictionary - so changing one of them would change them all. Since...
Differences between std::make_unique and std::unique_ptr with new
... unique_ptr<U>(new U())); // unsafe*
The addition of make_unique finally means we can tell people to 'never' use new rather than the previous rule to "'never' use new except when you make a unique_ptr".
There's also a third reason:
make_unique does not require redundant type usage. unique...
What is a good use case for static import of methods?
...e your program unreadable and unmaintainable, polluting its namespace with all the static members you import. Readers of your code (including you, a few months after you wrote it) will not know which class a static member comes from. Importing all of the static members from a class can be particular...
Adding two Java 8 streams, or an extra element to a stream
...ream.concat(lhs, Stream.of(rhs));
}
With these two static methods (optionally in combination with static imports), the two examples could be written as follows:
Stream<Foo> stream = concat(stream1, concat(stream2, element));
Stream<Foo> stream = concat(
conca...