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Pass correct “this” context to setTimeout callback?
...or this case, for map(), for forEach(), etc., etc., using less code, fewer CPU cycles, and less memory. ***See: Misha Reyzlin's answer.
– HoldOffHunger
Oct 20 '17 at 17:06
ad...
What is the performance cost of having a virtual method in a C++ class?
...3ghz in-order PowerPC processor. On that architecture, a virtual function call costs 7 nanoseconds longer than a direct (non-virtual) function call.
So, not really worth worrying about the cost unless the function is something like a trivial Get()/Set() accessor, in which anything other than inli...
What's the state of the art in email validation for Rails?
... answered Aug 24 '10 at 9:56
HallelujahHallelujah
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Difference between java.util.Random and java.security.SecureRandom
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The standard Oracle JDK 7 implementation uses what's called a Linear Congruential Generator to produce random values in java.util.Random.
Taken from java.util.Random source code (JDK 7u2), from a comment on the method protected int next(int bits), which is the one that genera...
How do I replace NA values with zeros in an R dataframe?
...then assign it to the location/name on the left. In this case, we aren't really "doing" anything - just making zeroes. The left side is saying: look at the d object, inside the d object (the square brackets), find all the elements that return TRUE (is.na(d) returns a logical for each element). Once...
Wi-Fi 是什么的缩写 - 程序人生、谈天论地 - 清泛IT论坛，有思想、有深度
...试产品是否符合标准，导致 802.11 产品间的互通频频出现问题，而联盟的成立就是为了填补这一空缺。联盟还将推广符合 802.11 标准的无线网络技术作为己任，因此他们认为需要一个朗朗上口的名字来代替拗口的专业术语（呃…...
Is there a performance impact when calling ToList()?
...on) constructor. This constructor must make a copy of the array (more generally IEnumerable<T>), otherwise future modifications of the original array will change on the source T[] also which wouldn't be desirable generally.
I would like to reiterate this will only make a difference with a hu...
PHP & mySQL: Year 2038 Bug: What is it? How to solve it?
.... Instead of asking my question in bulk, I preferred to break it up into small parts so that it is easy for novice users to understand as well. So my question(s):
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Using Phonegap for Native Application development [closed]
... is forum's experience with Phonegap. What are the pain points and is it really scalable for enterprise level application development.
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App Inventor 2 列表积木完全指南：从入门到精通，一篇搞定数据存储 - App...
做 App 的时候，你一定会遇到这样一个问题：数据太多了，变量根本管不过来。 比如一个购物清单有 20 样商品，难道要建 20 个变量？一个用户通讯录有 100 条记录，难道要写 100 个变量？当然不用。列表（Lists） 就是帮你批量管...