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Callback functions in Java
Is there a way to pass a call back function in a Java method?
17 Answers
17
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In Javascript, how to conditionally add a member to an object?
I would like to create an object with a member added conditionally.
The simple approach is:
22 Answers
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Get records with max value for each group of grouped SQL results
... a super-simple way to do this in mysql:
select *
from (select * from mytable order by `Group`, age desc, Person) x
group by `Group`
This works because in mysql you're allowed to not aggregate non-group-by columns, in which case mysql just returns the first row. The solution is to first order the ...
Difference between declaring variables before or in loop?
I have always wondered if, in general, declaring a throw-away variable before a loop, as opposed to repeatedly inside the loop, makes any (performance) difference?
A (quite pointless) example in Java:
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What is more efficient? Using pow to square or just multiply it with itself?
What of these two methods is in C more efficient? And how about:
7 Answers
7
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SQL JOIN and different types of JOINs
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TylerH
18.1k1212 gold badges6161 silver badges8080 bronze badges
answered Nov 30 '13 at 9:34
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Does JavaScript have “Short-circuit” evaluation?
...rcuit" evaluation.
if (true == true || foo.foo){
// Passes, no errors because foo isn't defined.
}
Live DEMO
if (false && foo.foo){
// Passes, no errors because foo isn't defined.
}
Live DEMO
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Shuffling a list of objects
I have a list of objects and I want to shuffle them. I thought I could use the random.shuffle method, but this seems to fail when the list is of objects. Is there a method for shuffling objects or another way around this?
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pandas three-way joining multiple dataframes on columns
...g) names of people, while all the other columns in each dataframe are attributes of that person.
10 Answers
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What is the purpose of Rank2Types?
I am not really proficient in Haskell, so this might be a very easy question.
6 Answers
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