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Should try…catch go inside or outside a loop?
...ly no performance difference in where the try/catch structures are placed. Internally, they are implemented as a code-range table in a structure that is created when the method is called. While the method is executing, the try/catch structures are completely out of the picture unless a throw occurs,...
Returning unique_ptr from functions
...the object were designated by an rvalue.
Just wanted to add one more point that returning by value should be the default choice here because a named value in the return statement in the worst case, i.e. without elisions in C++11, C++14 and C++17 is treated as an rvalue. So for example the follo...
Cleaning `Inf` values from an R dataframe
...ar)
dat %>% rationalize()
Which return a data frame with all Inf are converted to NA.
Timings compared to some above solutions. Code:
library(hablar)
library(data.table)
dat <- data.frame(a = rep(c(1,Inf), 1e6), b = rep(c(Inf,2), 1e6),
c = rep(c('a','b'),1e6),d = rep(c(...
Will using goto leak variables?
...abels).
1. Label scope
You can't jump across functions:
void f() {
int x = 0;
goto lol;
}
int main() {
f();
lol:
return 0;
}
// error: label 'lol' used but not defined
[n3290: 6.1/1]: [..] The scope of a label is the function in which
it appears. [..]
2. Object initiali...
What is a “context bound” in Scala?
... to Scala 2.7, tabulate could be
written as follows:
def tabulate[T](len: Int, f: Int => T) = {
val xs = new Array[T](len)
for (i <- 0 until len) xs(i) = f(i)
xs
}
In Scala 2.8 this is no longer possible, because runtime information is necessary to create the right representatio...
Quicksort vs heapsort
...hough there remains
the chance of worst case performance
except in the introsort variant, which
switches to heapsort when a bad case
is detected. If it is known in advance
that heapsort is going to be
necessary, using it directly will be
faster than waiting for introsort to
switch to...
Representing Directory & File Structure in Markdown Syntax [closed]
...
brew install dos2unix
dos2unix lib/node_modules/mddir/src/mddir.js
This converts line endings to Unix instead of Dos
Then run as normal with: node mddir "../relative/path/".
Example generated markdown file structure 'directoryList.md'
|-- .bowerrc
|-- .jshintrc
|-- .jshintrc2
|...
Altering a column to be nullable
...s):
ALTER TABLE Merchant_Pending_Functions ALTER COLUMN NumberOfLocations INT NULL
Replace INT with your actual datatype.
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How can I generate random number in specific range in Android? [duplicate]
...
Random r = new Random();
int i1 = r.nextInt(80 - 65) + 65;
This gives a random integer between 65 (inclusive) and 80 (exclusive), one of 65,66,...,78,79.
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C++11 tuple 这一篇就够了 - C/C++ - 清泛网 - 专注C/C++及内核技术
...法：
#include <iostream>
#include <tuple>
#include <functional>
int main()
{
auto t1 = std::make_tuple(10, "Test", 3.14);
std::cout << "The value of t1 is "
<< "(" << std::get<0>(t1) << ", " << std::get<1>(t1)
<< ", " << std::get<2>(t1) << ")\n";
...