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Map vs Object in JavaScript
I just discovered chromestatus.com and, after losing several hours of my day, found this feature entry :
12 Answers
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Difference between Activity and FragmentActivity
I was working on fragments and came across two things Activity and FragmentActivity which are used several times. I want to know that is there any difference between these two, because when I changed Activity with FragmentActivity , it had no effect on the app.
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How to check for an undefined or null variable in JavaScript?
...xistingObj.someUndefProperty. An undefined property doesn't yield an error and simply returns undefined, which, when converted to a boolean, evaluates to false. So, if you don't care about
0 and false, using if(obj.undefProp) is ok. There's a common idiom based on this fact:
value = obj.prop || de...
How to set up Spark on Windows?
...s guide: http://spark.apache.org/docs/latest/building-spark.html
Download and install Maven, and set MAVEN_OPTS to the value specified in the guide.
But if you're just playing around with Spark, and don't actually need it to run on Windows for any other reason that your own machine is running Wind...
What is the difference between a .xib file and a .storyboard?
Can someone explain in simple words the difference between .xib and .storyboard?
6 Answers
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Writing a dict to txt file and reading it back?
...mes not recommended. The problem is that eval() will evaluate any string, and if someone tricked you into running a really tricky string, something bad might happen. In this case, you are just running eval() on your own file, so it should be okay.
But because eval() is useful, someone made an alt...
What is the id( ) function used for?
I read the Python 2 docs and noticed the id() function:
13 Answers
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Difficulty with ng-model, ng-repeat, and inputs
I am trying to allow the user to edit a list of items by using ngRepeat and ngModel . ( See this fiddle .) However, both approaches I've tried lead to bizarre behavior: one doesn't update the model, and the other blurs the form on each keydown.
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What is the difference between Reader and InputStream?
What is the difference between Reader and InputStream?
And when to use what?
If I can use Reader for reading characters why I will use inputstream, I guess to read objects?
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Returning a C string from a function
...Other languages (Java, Pascal, etc.) use different methodologies to understand "my string".
If you ever use the Windows API (which is in C++), you'll see quite regularly function parameters like: "LPCSTR lpszName". The 'sz' part represents this notion of 'string-zero': an array of bytes with a null...