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What is null in Java?
...ceof operator is true if the value of the RelationalExpression is not null and the reference could be cast to the ReferenceType without raising a ClassCastException. Otherwise the result is false.
This means that for any type E and R, for any E o, where o == null, o instanceof R is always false.
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Gem::LoadError for mysql2 gem, but it's already in Gemfile
...his question by me 8 September 2015 so use the above line in your Gem file and run:
bundle install
You should be good to go
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how to use javascript Object.defineProperty
...ed to find EVERY occurence of the discount modification in the client code and add a line
if(obj.discount>80) obj.discount = 80;
Then the e-shop owner may further change his strategy, like "if the customer is reseller, the maximal discount can be 90%". And you need to do the change on multiple...
Best way to initialize (empty) array in PHP
...o = [] rather than var foo = new Array() for reasons of object creation and instantiation. I wonder whether there are any equivalences in PHP?
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Windows: XAMPP vs WampServer vs EasyPHP vs alternative [closed]
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I generally install Apache + PHP + MySQL by-hand, not using any package like those you're talking about.
It's a bit more work, yes; but knowing how to install and configure your environment is great -- and useful.
The first time, you'll need maybe half a day or a day ...
How to tell if node.js is installed or not
I've recently installed node.js and I have no idea how to run applications. I installed node.js but couldn't find further instructions. What does one really need to do? I wanted to see if it was actually working. So I executed a script called hello.js. It went as such:
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The model backing the context has changed since the database was created
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I've changed my production db manually and turned off the migration and it works, Thanks
– Mohsen Afshin
Sep 10 '12 at 21:05
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How do you unit test private methods?
...e code. Since Release code is optimized, you might see different behavior and different timings. In multithreaded code this means your unit tests won't appropriately detect race conditions. Much better is to use reflection via @AmazedSaint's suggestion below or use the built-in PrivateObject/Priv...
How to print like printf in Python3?
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In both versions, % is an operator which requires a string on the left-hand side and a value or a tuple of values or a mapping object (like dict) on the right-hand side.
So, your line ought to look like this:
print("a=%d,b=%d" % (f(x,n),g(x,n)))
Also, the recommendation for Python3 and newer ...
git: Your branch is ahead by X commits
...ng a repository on google code. Then I cloned this repository on my laptop and I do work there and push the changes, laptop => code.google. I used to get this message on my server where I had created a clone of code.google code repository and I used to pull the changes. I think fetch is required ...