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What is a lambda (function)?

...an primitive type. Predicate<Integer> pred = x -> x % 2 == 0; // Tests if the parameter is even. boolean result = pred.test(4); // true Lua adder = function(x) return function(y) return x + y end end add5 = adder(5) add5(1) == 6 -- true Kotlin val pred = { x: I...
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How to check for an undefined or null variable in JavaScript?

... I think the most efficient way to test for "value is null or undefined" is if ( some_variable == null ){ // some_variable is either null or undefined } So these two lines are equivalent: if ( typeof(some_variable) !== "undefined" && some_variab...
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How do I prevent commands from showing up in Bash history?

...tory (as well as duplicates). For example: $ HISTCONTROL=ignoreboth $ echo test1 $ echo test2 $ history | tail -n2 1015 echo test1 1016 history | tail -n2 Here is what man bash says: HISTCONTROL A colon-separated list of values controlling how commands are saved on the history list. If the l...
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java.lang.ClassNotFoundException: org.springframework.web.servlet.DispatcherServlet

...upId>org.springframework</groupId> <artifactId>spring-test</artifactId> <version>${spring.version}</version> <scope>test</scope> </dependency> <dependency> <groupId>junit</groupId> <artifac...
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c# datatable to csv

...rray(); sb.AppendLine(string.Join(",", fields)); } File.WriteAllText("test.csv", sb.ToString()); .net >= 4.0 And as Tim pointed out, if you are on .net>=4, you can make it even shorter: StringBuilder sb = new StringBuilder(); IEnumerable<string> columnNames = dt.Columns.Cast&l...
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HTML5 Canvas vs. SVG vs. div

...t the benefits of each, but I will give some of the relevant results of my tests to consider for your specific application: I made Canvas and HTML DIV test pages, both had movable "nodes." Canvas nodes were objects I created and kept track of in Javascript. HTML nodes were movable Divs. I added 10...
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When does static class initialization happen?

...extual order as defined in the class. Consider the example: public class Test { static String sayHello() { return a; } static String b = sayHello(); // a static method is called to assign value to b. // but its a has not been initialized yet. ...
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How do I properly escape quotes inside HTML attributes?

... " is the correct way, the third of your tests: <option value=""asd">test</option> You can see this working below, or on jsFiddle. alert($("option")[0].value); <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.mi...
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Ignore invalid self-signed ssl certificate in node.js with https.request?

... I was having trouble with running tests using mocha on my self-signed https node server, and adding this immediately before any describe blocks made my tests pass. – artis3n Jul 30 '15 at 14:33 ...
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How can I list ALL DNS records?

...$2"; shift 2 ;; *) break ;; esac; done DOM="$1"; shift TYPE="${1:-any}" test "${NS:-}" || NS=$(dig +short SOA "$DOM" | awk '{print $1}') test "$NS" && NS="@$NS" if test "$EXTENDED"; then dig +nocmd $NS "$DOM" +noall +answer "$TYPE" wild_ips=$(dig +short "$NS" "*.$DOM" "$TYPE" | tr '...