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Why is the default value of the string type null instead of an empty string?
It's quite annoying to test all my strings for null before I can safely apply methods like ToUpper() , StartWith() etc...
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How to prevent Node.js from exiting while waiting for a callback?
...re empty. A callback is added to an event queue when a call such as
emmiter1.on('this_event',callback).
has executed. This call is part of the code written by the module developer .
If a module is a quick port from a synchronous/blocking version, this may not happen til some part of the oper...
Container-fluid vs .container
...he viewport that the webpage is being viewed on, the container class gives its div a specific fixed width. These lines don't exist in any form for container-fluid, so its width changes every time the viewport width changes.
So for example, say your browser window is 1000px wide. As it's greater tha...
How do you determine what technology a website is built on? [closed]
Quite often I come across a nice looking or functional website, and wonder what technology was used to create it. What techniques are available to figure out what a
particular website was built with?
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Difference between HashMap, LinkedHashMap and TreeMap
...ee classes implement the Map interface and offer mostly the same functionality. The most important difference is the order in which iteration through the entries will happen:
HashMap makes absolutely no guarantees about the iteration order. It can (and will) even change completely when new element...
Why is Multiple Inheritance not allowed in Java or C#?
I know that multiple inheritance is not allowed in Java and C#. Many books just say, multiple inheritance is not allowed. But it can be implemented by using interfaces. Nothing is discussed about why it is not allowed. Can anybody tell me precisely why it is not allowed?
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glVertexAttribPointer clarification
...ust want to make sure I understand this correctly (I'd ask on SO Chat, but it's dead in there!):
2 Answers
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What is the difference between the | and || or operators?
...ke the & and && operator, the double Operator is a "short-circuit" operator.
For example:
if(condition1 || condition2 || condition3)
If condition1 is true, condition 2 and 3 will NOT be checked.
if(condition1 | condition2 | condition3)
This will check conditions 2 and 3, even if 1...
How can you find the height of text on an HTML canvas?
...has a context.measureText(text) function that will tell you how much width it would require to print that text, but I can't find a way to find out how tall it is. I know it's based on the font, but I don't know to convert a font string to a text height.
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Receive result from DialogFragment
I am using DialogFragments for a number of things: choosing item from list, entering text.
13 Answers
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