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Match multiple cases classes in scala

... matcher(l: Foo): String = { l match { case A() => "A" case B(_) | C(_) => "B" case _ => "default" } } If you must, must, must extract the parameter and treat them in the same code block, you could: def matcher(l: Foo): String = { l match { case A() => "A" ca...
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Can an Option in a Select tag carry multiple values?

... I was actually wondering this today, and I achieved it by using the php explode function, like this: HTML Form (in a file I named 'doublevalue.php': <form name="car_form" method="post" action="doublevalue_action.php"> ...
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How can I add or update a query string parameter?

... @JarónBarends - Tweak value check to check against undefined and null to allow setting 0 values Third Update There was a bug where removing a querystring variable directly before a hashtag would lose the hashtag symbol which has been fixed Fourth Update Thanks @rooby for pointing out a regex o...
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What is a stored procedure?

... a couple of ways. Most major DBMs support stored procedures; however, not all do. You will need to verify with your particular DBMS help documentation for specifics. As I am most familiar with SQL Server I will use that as my samples. To create a stored procedure the syntax is fairly simple: CRE...
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A Regex that will never be matched by anything

... This is actually quite simple, although it depends on the implementation / flags*: $a Will match a character a after the end of the string. Good luck. WARNING: This expression is expensive -- it will scan the entire line, find the en...
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In Python how should I test if a variable is None, True or False

... a = 'foo' if a: print 'its true' a is not actually TRUE, it's just not none – wesm Apr 3 '15 at 21:06 ...
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Haml: Control whitespace around text

...t;a href='thing'>here</a>. precede: = precede '*' do %span.small Not really Produces: *<span class='small'>Not really</span> To answer the original question: I will first = succeed ',' do = link_to 'link somewhere', 'http://example.com' - if @condition then render...
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Why no generics in Go?

... id types. Type information is preserved and can be "cast" (asserted, actually) back to its concrete type. Get the gritty details here: golang.org/ref/spec#Type_assertions – tbone Aug 25 '13 at 20:50 ...
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how to create a file name with the current date & time in python?

... human readable. from datetime import datetime datetime.now().strftime("%Y_%m_%d-%I_%M_%S_%p") '2020_08_12-03_29_22_AM' share | improve this answer | follow ...
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How to rethrow InnerException without losing stack trace in C#?

I am calling, through reflection, a method which may cause an exception. How can I pass the exception to my caller without the wrapper reflection puts around it? I am rethrowing the InnerException, but this destroys the stack trace. Example code: ...