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Use of def, val, and var in scala
... new Person("Kumar",12) . If I use var or val the output is 20 . I understand the default is val in scala. This:
6 Answers...
PHP: How to use array_filter() to filter array keys?
...in strings.
You can also use ARRAY_FILTER_USE_BOTH to have both the value and the key passed to your filter function. Here's a contrived example based upon the first, but note that I'd not recommend encoding filtering rules using $allowed this way:
$my_array = ['foo' => 1, 'bar' => 'baz', 'h...
How do I query between two dates using MySQL?
... is before your first date (ie. you are querying between September 29 2010 and January 30 2010). Try reversing the order of the dates:
SELECT *
FROM `objects`
WHERE (date_field BETWEEN '2010-01-30 14:15:55' AND '2010-09-29 10:15:55')
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how to read System environment variable in Spring applicationContext
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-Dprop=... sets a java property in command line. You can read this property via System.getProperty("prop"). If you would like to read a OS property then use System.getenv("os-env-variable"). See javadoc: docs.oracle.com/javase/6/docs/api/java/lang/System.html
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HttpServletRequest to complete URL
...king a defensive copy that's a very good way to introduce strange behavior and bugs in other parts of code that expect it in it's original form.
– Ken Blair
May 22 '12 at 16:53
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DateTime.ToString() format that can be used in a filename or extension?
...d but most of the DateTime methods I've tried output something with spaces and slashes. For instance:
8 Answers
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How to merge a list of lists with same type of items to a single list of items?
...tMany(x => x.SelectMany(y => y)).ToList();
– Brandon Kramer
Apr 3 '17 at 14:01
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C++ where to initialize static const
...// No definition for i. (*)
const int foo::j = 4;
(*) According to the standards you must define i outside of the class definition (like j is) if it is used in code other than just integral constant expressions. See David's comment below for details.
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Why do you use typedef when declaring an enum in C++?
I haven't written any C++ in years and now I'm trying to get back into it. I then ran across this and thought about giving up:
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How can I determine if a variable is 'undefined' or 'null'?
...}
Because null == undefined is true, the above code will catch both null and undefined.
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