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Ruby / Rails - Change the timezone of a Time, without changing the value
I have a record foo in the database which has :start_time and :timezone attributes.
11 Answers
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What's the absurd function in Data.Void useful for?
...little bit hard, since Haskell is non strict. The general use case is to handle impossible paths. For example
simple :: Either Void a -> a
simple (Left x) = absurd x
simple (Right y) = y
This turns out to be somewhat useful. Consider a simple type for Pipes
data Pipe a b r
= Pure r
| A...
Why do people say there is modulo bias when using a random number generator?
...it. So I am going to post one here which will hopefully help people understand why exactly there is "modulo bias" when using a random number generator, like rand() in C++.
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Exposing a port on a live Docker container
...now I can use the EXPOSE instruction inside a Dockerfile to expose a port, and I can use the -p flag with docker run to assign ports, but once a container is actually running, is there a command to open/map additional ports live?
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What is the difference between IEqualityComparer and IEquatable?
I want to understand the scenarios where IEqualityComparer<T> and IEquatable<T> should be used.
The MSDN documentation for both looks very similar.
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Difference between fold and reduce?
...ing to learn F# but got confused when trying to distinguish between fold and reduce . Fold seems to do the same thing but takes an extra parameter. Is there a legitimate reason for these two functions to exist or they are there to accommodate people with different backgrounds? (E.g.: String and...
How to pass a function as a parameter in Java? [duplicate]
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Java 8 and above
Using Java 8+ lambda expressions, if you have a class or interface with only a single abstract method (sometimes called a SAM type), for example:
public interface MyInterface {
String doSomething(int param1, S...
What is the difference between char array and char pointer in C?
I am trying to understand pointers in C but I am currently confused with the following:
8 Answers
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Where IN clause in LINQ [duplicate]
...s = tooManyStates.Where(s => s.In("x", "y", "z"));
Feels more natural and closer to sql.
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How do I find duplicates across multiple columns?
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Duplicated id for pairs name and city:
select s.id, t.*
from [stuff] s
join (
select name, city, count(*) as qty
from [stuff]
group by name, city
having count(*) > 1
) t on s.name = t.name and s.city = t.city
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