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Check if a method exists
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You're looking for respondsToSelector:-
if ([foo respondsToSelector: @selector(bar)] {
[foo bar];
}
As Donal says the above tells you that foo can definitely handle receiving the bar selector. However, if foo's a proxy that forwards bar to some underlying object tha...
Why would I ever use push_back instead of emplace_back?
...ob is to generate the code you wrote. The optimizing compiler's job is actually to generate the code you would have written if you were an expert on platform-specific optimizations and did not care about maintainability, just performance.
The actual difference between these two statements is that t...
Hidden Features of MySQL
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Since you put up a bounty, I'll share my hard won secrets...
In general, all the SQLs I tuned today required using sub-queries. Having come from Oracle database world, things I took for granted weren’t working the same with MySQL. And my reading on MySQL tuning makes me conclude that MySQL is be...
How to check if a value exists in an array in Ruby
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Let me just note that internally, #include? still does perform looping. The coder is saved from writing the loop explicitly, though. I have added an answer that performs the task truly without looping.
– Boris Stitnicky
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Regular expression to match a word or its prefix
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Square brackets are meant for character class, and you're actually trying to match any one of: s, |, s (again), e, a, s (again), o and n.
Use parentheses instead for grouping:
(s|season)
or non-capturing group:
(?:s|season)
Note: Non-capture groups tell the engine that it doesn...
What's the difference between getPath(), getAbsolutePath(), and getCanonicalPath() in Java?
...te path.
Converting from a path to a canonical path makes it absolute (usually tack on the current working directory so e.g. ./file.txt becomes c:/temp/file.txt). The canonical path of a file just "purifies" the path, removing and resolving stuff like ..\ and resolving symlinks (on unixes).
Also ...
How to exclude a module from a Maven reactor build?
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@SaM Actually, as of Maven 3.0.5 the Reactor will take in account the order in 'modules', although the order dictated by dependencies is of a higher priority.
– hellodanylo
Jul 29 '13 at 11:23
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Why can't static methods be abstract in Java?
.... static doesn't mean "not empty" -- that's just a consequence of Java not allowing static methods to be abstract. It means "callable on the class." (It should mean "callable only on the class" but that's another issue.) If Java supported abstract static methods I'd expect it to mean that the method...
Fix a Git detached head?
...ed HEAD
Run git branch tmp - this will save your changes in a new branch called tmp.
Run git checkout master
If you would like to incorporate the changes you made into master, run git merge tmp from the master branch. You should be on the master branch after running git checkout master.
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How to check for a JSON response using RSpec?
...en you can make your assertions against that parsed content.
parsed_body["foo"].should == "bar"
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