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LEFT OUTER joins in Rails 3
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what if you only wanted the Posts which had no user?
– mcr
Aug 18 '11 at 4:30
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What is the best way to concatenate two vectors?
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This is precisely what the member function std::vector::insert is for
std::vector<int> AB = A;
AB.insert(AB.end(), B.begin(), B.end());
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Java default constructor
What exactly is a default constructor — can you tell me which one of the following is a default constructor and what differentiates it from any other constructor?
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What is the C++ function to raise a number to a power?
...t;cmath>
pow(2,3)
if you're on a unix-like system, man cmath
Is that what you're asking?
Sujal
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What is the difference between square brackets and parentheses in a regex?
... that regex is trying to match << or >> or [[ or ]]. But from what you've said, it should be matching < or > or [ or ]. If you use | between [], do the brackets behave differently?
– Daniel Kaplan
Nov 14 '17 at 20:39
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Should __init__() call the parent class's __init__()?
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If you need something from super's __init__ to be done in addition to what is being done in the current class's __init__, you must call it yourself, since that will not happen automatically. But if you don't need anything from super's __init__, no need to call it. Example:
>>> class...
How do I delete everything in Redis?
...ing out" but that is followed by "give me a blank database"--regardless of what he actually meant, i think the distinction you made is useful, to say the least.
– doug
Aug 1 '11 at 2:47
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What's the best way to retry an AJAX request on failure using jQuery?
...n fail
$.ajax({
type : 'GET',
url : 'http://www.whatever123.gov',
timeout : 2000,
retries : 3, // <-------- Optional
retryInterval : 2000 // <-------- Optional
})
// Problem: "fail" will only be called once, and not for each ...
Coalesce function for PHP?
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What about multiple ternary shortcuts, would something like "echo $a ?: $b ?: $c ?: $d;" work?
– ChrisR
Mar 26 '10 at 13:55
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What are the Android SDK build-tools, platform-tools and tools? And which version should be used?
...There seems to be no official page explaining all the build tools. Here is what the Android team says about this.
The [build] tools, such as aidl, aapt, dexdump, and dx, are
typically called by the Android build tools or Android Development
Tools (ADT), so you rarely need to invoke these too...