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typeof !== “undefined” vs. != null
...e would use the !== or === operators when comparing a value whose type is known to be a string.
– Nicolas Rinaudo
Aug 30 '13 at 7:38
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Preferred way to create a Scala list
...odify it, use a tail recursive method, and probably others that I don't know about.
10 Answers
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FIND_IN_SET() vs IN()
..."aname".
Let's take table B which has columns named "bid","bname","aids".
Now there are dummy values in Table A and Table B as below.
Table A
aid aname
1 Apple
2 Banana
3 Mango
Table B
bid bname aids
1 Apple 1,2
2 Banana 2,1
3 Mango 3,1,2
enter code here
Case...
How to rethrow the same exception in SQL Server
...ce a reraise command, or the ability to catch only certain errors. But for now, use a workaround. Sorry.
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Regular expression to match a word or its prefix
...e non-capturing was what I needed. I thought using () would always match, knowing there is an option not to match is handy, Thank you.
– NMGod
Aug 23 '13 at 12:19
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How to clear the cache of nginx?
... is cacheable as well. If you have removed a page (404 or other errors are now served by the backend), the page now sends a Set-Cookie or a "Content-Control: private" header, the cached content will not be "invalidated".
– rbu
Feb 2 '16 at 10:17
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Could not change executable permissions on the application
...n't advise them to do that !!! Exactly what I want to avoid. I don't even know who my users are. The upgrade has not been released (approved but not released).
– Fraggle
Sep 30 '12 at 19:35
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How do you find out the type of an object (in Swift)?
...es, it's useful to be able to actually find out what type something is. I know the debugger can show you some type information, and you can usually rely on type inference to get away with not specifying the type in those situations, but still, I'd really like to have something like Python's type()
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Form inside a table
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Seems "in development" now, and ok to use
– user1156544
Jun 19 '17 at 13:47
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How to check a not-defined variable in JavaScript
...-assignable was fixed in ECMAScript 5, which was released in 2009. You can now safely use === and !== to test for undefined without using typeof as undefined has been read-only for some time.
If you want to know if a member exists independent but don't care what its value is:
if ('membername' in o...