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What is the difference between “def” and “val” to define a function
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Method def even evaluates on call and creates new function every time (new instance of Function1).
def even: Int => Boolean = _ % 2 == 0
even eq even
//Boolean = false
val even: Int => Boolean = _ % 2 == 0
even eq even
//Boolean = true
With def you ...
Array vs. Object efficiency in JavaScript
I have a model with possibly thousands of objects. I was wondering what would be the most efficient way of storing them and retrieving a single object once I have it's id. The id's are long numbers.
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Why use static_cast(x) instead of (int)x?
...l static_cast<>(), reinterpret_cast<>(), const_cast<>(), and dynamic_cast<>(). These four things are completely different.
A static_cast<>() is usually safe. There is a valid conversion in the language, or an appropriate constructor that makes it possible. The only tim...
Correct way to load a Nib for a UIView subclass
...ware this question has been asked before but the answers are contradicting and I am confused, so please don't flame me.
6 A...
Failed to allocate memory: 8
From today, when I tried to run an app in NetBeans on a 2.3.3 Android platform, it shows me that:
20 Answers
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Select n random rows from SQL Server table
...th about 50,000 rows in it. I want to select about 5,000 of those rows at random. I've thought of a complicated way, creating a temp table with a "random number" column, copying my table into that, looping through the temp table and updating each row with RAND() , and then selecting from that table...
Purpose of Trigraph sequences in C++?
According to C++'03 Standard 2.3/1:
9 Answers
9
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How to save and restore multiple different sessions in Vim?
...like
:mksession ~/mysession.vim
Then later you can source that vim file and you'll have your old session back:
:source ~/mysession.vim
or open vim with the -S option:
$ vim -S ~/mysession.vim
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What is the JavaScript version of sleep()?
...esolve or reject).
Compatibility
promises are supported in Node v0.12+ and widely supported in browsers, except IE
async/await landed in V8 and has been enabled by default since Chrome 55 (released in Dec 2016)
it landed in Node 7 in October 2016
and also landed in Firefox Nightly in November ...
Why doesn't git recognize that my file has been changed, therefore git add not working
... trying to push my files to github using bash. They are already on there, and I am uploading a newer version with new lines and code, etc. But when I try git add and then git status it says:
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