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What are some resources for getting started in operating system development? [closed]
...of the day the bootloader takes the machine code of the kernel, puts it in memory, and jumps to it. You can put any machine code in the kernel that you want, but most C programs expect an OS so you'll need to tell your compiler that it won't have all that, or the bootloader has to create some of it...
What does a \ (backslash) do in PHP (5.3+)?
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\ (backslash) is the namespace separator in PHP 5.3.
A \ before the beginning of a function represents the Global Namespace.
Putting it there will ensure that the function called is from the global namespace, even if there is a function by the ...
Group by multiple columns in dplyr, using string vector input
...nce this question was posted, dplyr added scoped versions of group_by (documentation here). This lets you use the same functions you would use with select, like so:
data = data.frame(
asihckhdoydkhxiydfgfTgdsx = sample(LETTERS[1:3], 100, replace=TRUE),
a30mvxigxkghc5cdsvxvyv0ja = sample(LET...
NSDate get year/month/day
...given no other information? I realize that I could probably do this with something similar to this:
17 Answers
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What is the difference between And and AndAlso in VB.NET?
...en
' bla bla
End If
This one does not throw an exception.
So if you come from the C# world, you should use AndAlso like you would use &&.
More info here: http://www.panopticoncentral.net/2003/08/18/the-ballad-of-andalso-and-orelse/
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Using boolean values in C
...t. Choose this if possible.
Options 2, 3 and 4 will have in practice the same identical behavior. #2 and #3 don't use #defines though, which in my opinion is better.
If you are undecided, go with #1!
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jQuery: Selecting by class and input type
I would like to select a set of elements that are both of a certain input type (say, a checkbox) and have a certain class using jQuery. However, when I try the following:
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Generating random whole numbers in JavaScript in a specific range?
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There are some examples on the Mozilla Developer Network page:
/**
* Returns a random number between min (inclusive) and max (exclusive)
*/
function getRandomArbitrary(min, max) {
return Math.random() * (max - min) + min;
}
/**
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Does Typescript support the ?. operator? (And, what's it called?)
... "accessor variant" of the existential operator).
From CoffeeScript's documentation on Operators:
The accessor variant of the existential operator ?. can be used to soak up null references in a chain of properties. Use it instead of the dot accessor . in cases where the base value may be null o...
How to check for an active Internet connection on iOS or macOS?
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Important: This check should always be performed asynchronously. The majority of answers below are synchronous so be careful otherwise you'll freeze up your app.
Swift
1) Install via CocoaPods or Carthage: https://github.com/ashleymills/Reachability.swift
2) Test r...