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Uses for Optional
Having been using Java 8 now for 6+ months or so, I'm pretty happy with the new API changes. One area I'm still not confident in is when to use Optional . I seem to swing between wanting to use it everywhere something may be null , and nowhere at all.
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What is a NullReferenceException, and how do I fix it?
I have some code and when it executes, it throws a NullReferenceException , saying:
28 Answers
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How does a language expand itself? [closed]
...am learning C++ and I've just started learning about some of Qt 's capabilities to code GUI programs. I asked myself the following question:
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What is recursion and when should I use it?
...ems to come up regularly on mailing lists and online discussions is the merits (or lack thereof) of doing a Computer Science Degree. An argument that seems to come up time and again for the negative party is that they have been coding for some number of years and they have never used recursion.
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How does facebook, gmail send the real time notification?
...e pointless requests, because nothing has happened.
The way Facebook does it is using the comet approach, rather than polling on an interval, as soon as one poll completes, it issues another one. However, each request to the script on the server has an extremely long timeout, and the server only r...
Xamarin 2.0 vs Appcelerator Titanium vs PhoneGap [duplicate]
...til a day comes when everyone uses the same platform. Android?
HTML? WebKit? iOS? Windows? Xamarin? Titanum? PhoneGap? Corona? ecc.
Sometimes I hear it said that there are essentially two approaches
to cross-platform mobile apps. You can either use an embedded
browser control and write a...
How can I launch multiple instances of MonoDevelop on the Mac?
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On Mac, if you have an app open and you try to launch it again, the Mac just switches to the open app. You can force it to open a new instance by passing the option "-n" to the launcher. In a terminal, run
open -n /Applications/MonoDevelop.app
Note also that MonoDevelop is ca...
Focus-follows-mouse (plus auto-raise) on Mac OS X
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You can do it for Terminal.app by issuing the following command at the command line:
defaults write com.apple.Terminal FocusFollowsMouse -bool true
For X11 apps you can do this:
defaults write com.apple.x11 wm_ffm -bool true
In Sn...
Is Chrome's JavaScript console lazy about evaluating arrays?
I'll start with the code:
7 Answers
7
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Multiple glibc libraries on a single host
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It is very possible to have multiple versions of glibc on the same system (we do that every day).
However, you need to know that glibc consists of many pieces (200+ shared libraries) which all must match. One of the pieces i...