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Is there a “null coalescing” operator in JavaScript?

...an results in false, the assignment will use the second operand. Beware of all the cases below: alert(Boolean(null)); // false alert(Boolean(undefined)); // false alert(Boolean(0)); // false alert(Boolean("")); // false alert(Boolean("false")); // true -- gotcha! :) This means: var whatIWant = n...
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Understanding Canvas and Surface concepts

...nders these to the final display in their correct Z-order. A surface typically has more than one buffer (usually two) to do double-buffered rendering: the application can be drawing its next UI state while the surface flinger is compositing the screen using the last buffer, without needing to wait ...
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TypeError: not all arguments converted during string formatting python

The program is supposed to take in two names, and if they are the same length it should check if they are the same word. If it's the same word it will print "The names are the same" . If they are the same length but with different letters it will print "The names are different but the same length...
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What's “requestCode” used for on PendingIntent?

... the documentation doesn't say anything about it? Is it possible to remove all alarms of a certain type, no matter what is the requestCode? – android developer Feb 3 '14 at 12:36 ...
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How do you concatenate Lists in C#?

...you want to assign it to a variable that is List<T>, you'll have to call ToList() on the IEnumerable<T> that is returned. share | improve this answer | follow ...
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Why does (0 < 5 < 3) return true?

...d while I was editing my question to add the if(0 &lt; 5 &lt; 1) == false. All is clear now, thanks :) – punkrockbuddyholly Nov 3 '10 at 16:39 ...
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What makes Lisp macros so special?

...bleByTwo = [x for x in range(10) if x % 2 == 0] yields a list containing all even numbers between 0 and 9. Back in the Python 1.5 days there was no such syntax; you'd use something more like this: divisibleByTwo = [] for x in range( 10 ): if x % 2 == 0: divisibleByTwo.append( x ) Thes...
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SQL Server Management Studio won't let me add an index to a table

... "New Index" menu item is grayed out. I don't understand why. I've deleted all data in the table just in case, and refreshed and restarted SSMS, but no luck. I'm using SQL Server 2012 Business Intelligence SP1 CTP. ...
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How can I use grep to find a word inside a folder?

..., a directory is a kind of file (there is a term "regular file" to specifically refer to entities that are called just "files" in Windows). grep -nr string reads the content to search from the standard input, that is why it just waits there for input from you, and stops doing so when you press ^C (...
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Delete first character of a string in Javascript

..."foobar"; var s2 = s1.substring(1); alert(s2); // shows "oobar" To remove all 0's at the start of the string: var s = "0000test"; while(s.charAt(0) === '0') { s = s.substring(1); } share | improv...