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Returning a boolean from a Bash function
... want to write a bash function that check if a file has certain properties and returns true or false. Then I can use it in my scripts in the "if". But what should I return?
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Which characters are valid in CSS class names/selectors?
...racter is a hyphen, the second character must2 be a letter or underscore, and the name must be at least 2 characters long.
-?[_a-zA-Z]+[_a-zA-Z0-9-]*
In short, the previous rule translates to the following, extracted from the W3C spec.:
In CSS, identifiers (including element names, classes, ...
What is the difference between “long”, “long long”, “long int”, and “long long int” in C++?
I am transitioning from Java to C++ and have some questions about the long data type. In Java, to hold an integer greater than 2 32 , you would simply write long x; . However, in C++, it seems that long is both a data type and a modifier.
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What are the differences between BDD frameworks for Java? [closed]
What are the pros and cons of each Behavior Driven Development (BDD) framework for Java?
8 Answers
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Error during installing HAXM, VT-X not working
I am an entry-level Android software developer. I recently heard about HAXM that support emulator in rendering graphics more smoothly. I downloaded appropriate file HAXM file for Windows 7 64 bit, unpacked and started installing. However, during the installation process I get this error:
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java.lang.UnsupportedClassVersionError: Bad version number in .class file?
... suggestions on the web indicate that the code was compiled in one version and executed in another version (new on old). However, I only have one version of JRE on my system. If I run the commands:
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Why should I use a pointer rather than the object itself?
I'm coming from a Java background and have started working with objects in C++. But one thing that occurred to me is that people often use pointers to objects rather than the objects themselves, for example this declaration:
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What's “wrong” with C++ wchar_t and wstrings? What are some alternatives to wide characters?
...C++ community(particularly ##c++ on freenode) resent the use of wstrings and wchar_t , and their use in the windows api. What is exactly "wrong" with wchar_t and wstring , and if I want to support internationalization, what are some alternatives to wide characters?
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Convert Existing Eclipse Project to Maven Project
...ilds. Right now the procedure is far more complicated than it ought to be, and we're hoping that Maven will simplify things to a one-click build.
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Why doesn't 'ref' and 'out' support polymorphism?
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UPDATE: I used this answer as the basis for this blog entry:
Why do ref and out parameters not allow type variation?
See the blog page for more commentary on this issue. Thanks for the great question.
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Let's suppose you have classes Animal, Mammal, Reptile, Giraffe, Turtle and Ti...