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Is explicitly closing files important?
In Python, if you either open a file without calling close() , or close the file but not using try - finally or the " with " statement, is this a problem? Or does it suffice as a coding practice to rely on the Python garbage-collection to close all files? For example, if one does this:
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Why are Subjects not recommended in .NET Reactive Extensions?
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Ok,
If we ignore my dogmatic ways and ignore "subjects are good/bad" all together. Let us look at the problem space.
I bet you either have 1 of 2 styles of system you need to ingrate to.
The system raises an event or a call back when a message arrives
You need to poll the system to see if t...
Rails Root directory path?
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Personally I like the newer syntax: Rails.root / 'app' / 'assets' / 'images' / 'logo.png'
– Ajedi32
Feb 18 '16 at 17:13
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Does Dart support enumerations?
...ase Fruit.apple:
print('it is an apple');
break;
}
// get all the values of the enums
for (List<Fruit> value in Fruit.values) {
print(value);
}
// get the second value
print(Fruit.values[1]);
}
The old approach before 1.8:
class Fruit {
static const APPLE =...
Best way to test if a row exists in a MySQL table
...RE ...)
and per the documentation, you can SELECT anything.
Traditionally, an EXISTS subquery starts with SELECT *, but it could
begin with SELECT 5 or SELECT column1 or anything at all. MySQL
ignores the SELECT list in such a subquery, so it makes no difference.
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Why is GHC so large/big?
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It's a bit silly really. Every library that comes with GHC is provided in no less than 4 flavours:
static
dynamic
profiled
GHCi
The GHCi version is just the static version linked together in a single .o file. The other three versions all ...
Make a link open a new window (not tab) [duplicate]
... @JeanGkol I rewrote my answer to clarify the issue. Technically, it is working, because it opens a new browsing context (like it is supposed to do). The problem is, that in modern browsers "browsing context" is a tab instead of a window (you can change this in the settings though).
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What is the __DynamicallyInvokable attribute for?
...ble in DotPeek I notice that some methods are flavoured with a [__DynamicallyInvokable] attribute.
2 Answers
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Java's L number (long) specification
It appears that when you type in a number in Java, the compiler automatically reads it as an integer, which is why when you type in (long) 6000000000 (not in integer's range) it will complain that 6000000000 is not an integer. To correct this, I had to specify 6000000000L . I just learned abo...
When to use in vs ref vs out
...ss you need ref.
It makes a big difference when the data needs to be marshalled e.g. to another process, which can be costly. So you want to avoid marshalling the initial value when the method doesn't make use of it.
Beyond that, it also shows the reader of the declaration or the call whether the ...