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How to explain callbacks in plain english? How are they different from calling one function from ano
...cation needs to execute different functions based upon its context/state. For this, we use a variable where we would store the information about the function to be called. According to its need the application will set this variable with the information about function to be called and will call t...
How can I loop through a C++ map of maps?
...e remaining answers are outdated as of C++11 - you can use a ranged based for loop and simply do:
std::map<std::string, std::map<std::string, std::string>> mymap;
for(auto const &ent1 : mymap) {
// ent1.first is the first key
for(auto const &ent2 : ent1.second) {
// ent...
Is it a bad practice to catch Throwable?
...
You need to be as specific as possible. Otherwise unforeseen bugs might creep away this way.
Besides, Throwable covers Error as well and that's usually no point of return. You don't want to catch/handle that, you want your program to die immediately so that you can fix it prop...
jQuery: keyPress Backspace won't fire?
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Why would keyup fire for Backspace when keypress won't?
– Aaron Digulla
Jan 14 '11 at 11:11
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Providing a default value for an Optional in Swift?
The idiom for dealing with optionals in Swift seems excessively verbose, if all you want to do is provide a default value in the case where it's nil:
...
Start service in Android
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Probably you don't have the service in your manifest, or it does not have an <intent-filter> that matches your action. Examining LogCat (via adb logcat, DDMS, or the DDMS perspective in Eclipse) should turn up some warnings that may help.
More likely, you should start th...
How useful/important is REST HATEOAS ( maturity level 3)?
I'm getting involved in a project where some senior team members believe that a REST API has to be HATEOAS compliant and implement all Richardson's maturity levels ( http://martinfowler.com/articles/richardsonMaturityModel.html )!
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Why should we NOT use sys.setdefaultencoding(“utf-8”) in a py script?
...The encoding of py3k is hard-wired to "utf-8" and changing it raises an error.
I suggest some pointers for reading:
http://blog.ianbicking.org/illusive-setdefaultencoding.html
http://nedbatchelder.com/blog/200401/printing_unicode_from_python.html
http://www.diveintopython3.net/strings.html#one-ri...
Detecting an undefined object property
... check if an object does not actually have such a property, and will therefore return undefined by default when you try and access it:
if(!o.hasOwnProperty('myProperty')) {
alert("myProperty does not exist");
}
To check if the value associated with an identifier is the special value undefined, ...
What's the difference between parenthesis $() and curly bracket ${} syntax in Makefile?
... any differences in invoking variables with syntax ${var} and $(var) ? For instance, in the way the variable will be expanded or anything?
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