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Is pass-by-value a reasonable default in C++11?
...by value into functions and methods is slow for large objects, and is generally frowned upon. Instead, C++ programmers tend to pass references around, which is faster, but which introduces all sorts of complicated questions around ownership and especially around memory management (in the event that ...
Why can't the C# constructor infer type?
...type inference?
No. When you have
new Foo(bar)
then we could identify all types called Foo in scope regardless of generic arity, and then do overload resolution on each using a modified method type inference algorithm. We'd then have to create a 'betterness' algorithm that determines which of t...
MySQL: Fastest way to count number of rows
...olumn indexes, so it will be the best result. Mysql with MyISAM engine actually stores row count, it doensn't count all rows each time you try to count all rows. (based on primary key's column)
Using PHP to count rows is not very smart, because you have to send data from mysql to php. Why do it whe...
Tetris-ing an array
...a include the algorithm to find the longest common prefix, thus making actually using a tree structure unnecessary? Ie why check the tree for multiple children when you could detect that while building the tree. Why then a tree at all? I mean if you start with an array already. If you can change the...
How much faster is C++ than C#?
... more advanced JIT optimizations being complicated to implement, and the really cool ones are only arriving just now.
So C++ is faster, in many cases. But this is only part of the answer. The cases where C++ is actually faster, are highly optimized programs, where expert programmers thoroughly opti...
What does a tilde do when it precedes an expression?
...
~ is a bitwise operator that flips all bits in its operand.
For example, if your number was 1, its binary representation of the IEEE 754 float (how JavaScript treats numbers) would be...
0011 1111 1111 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0...
How do you detect Credit card type based on number?
...rds; there are other cards issued using the MasterCard system that do not fall into this IIN range. In 2016, they will add numbers in the range (222100-272099).
American Express: ^3[47][0-9]{5,}$ American Express card numbers start with 34 or 37.
Diners Club: ^3(?:0[0-5]|[68][0-9])[0-9]{4,}$ Dine...
decimal vs double! - Which one should I use and when? [duplicate]
...is inaccurate - it has relative accuracy and can represent very large or small magnitudes that decimal cannot handle at all.
– Michael Borgwardt
Jul 22 '09 at 15:14
77
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What do hjust and vjust do when making a plot using ggplot?
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I have tried that, and I get Error in grid.Call("L_textBounds", as.graphicsAnnot(x$label), x$x, x$y, : Polygon edge not found (zero-width or zero-height?) for vjust = .72 and higher.
– William Gunn
Sep 3 '11 at 0:48
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How to verify that a specific method was not called using Mockito?
How to verify that a method is not called on an object's dependency?
5 Answers
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