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Hidden features of Windows batch files
What are some of the lesser know, but important and useful features of Windows batch files?
91 Answers
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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...
Is it smart to replace boost::thread and boost::mutex with c++11 equivalents?
... is that my genius project manager thinks that boost is another dependency and that it is horrible because "you depend on it"(I tried explaining the quality of boost, then gave up after some time :( ). Smaller reason why I would like to do it is that I would like to learn c++11 features, because peo...
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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Saving an Object (Data persistence)
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You could use the pickle module in the standard library.
Here's an elementary application of it to your example:
import pickle
class Company(object):
def __init__(self, name, value):
self.name = name
self.value = value
with open('company_data....
How do I replace a character at a particular index in JavaScript?
I have a string, let's say Hello world and I need to replace the char at index 3. How can I replace a char by specifying a index?
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If vs. Switch Speed
...es a hash table to dispatch these. The hash table uses the strings as keys and delegates to the case codes as values.
This has asymptotic better runtime than lots of chained if tests and is actually faster even for relatively few strings.
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How to embed an autoplaying YouTube video in an iframe?
I am trying to embed the new iframe version of a YouTube video and get it to auto play.
14 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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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...