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C++11 range based loop: get item by value or reference to const
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If you don't want to change the items as well as want to avoid making copies, then auto const & is the correct choice:
for (auto const &x : vec)
Whoever suggests you to use auto & is wrong. Ignore them.
Here is recap:
Choose auto x when you want to work with copies.
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How to send commands when opening a tmux session inside another tmux session?
...ets screen display continue
A situation happens here, and @Paschalis provides a solution:
if it happens to be twice unlucky (a remote tmux session with C-q as prefix): Type Cltr-q, then :, and enter in tmux: send-keys C-q
Below it is the answer:
To make it simple, add the below line in yo...
What are all the possible values for HTTP “Content-Type” header?
I have to validate the Content-Type header value before passing it to an HTTP request.
4 Answers
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How do I automatically sort a has_many relationship in Rails?
...e adding a default order is cumbersome for some reason or you want to override your default in certain cases, it is trivial to specify it in the fetching action itself:
sorted = article.comments.order('created_at').all
sha...
Postgres: “ERROR: cached plan must not change result type”
...set_column_information will fix things in the short term if you want to avoid restarting.
– Grant Hutchins
Sep 20 '11 at 14:32
1
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Why are flag enums usually defined with hexadecimal values
...w.
Also, i'm not sure about C#, but I know that in C x << y is a valid compile-time constant.
Using bit shifts seems the most clear:
[Flags]
public enum MyEnum
{
None = 0,
Flag1 = 1 << 0,
Flag2 = 1 << 1,
Flag3 = 1 << 2,
Flag4 = 1 << 3,
Flag5 =...
Haskell: Where vs. Let
...Haskell and I am very confused by Where vs. Let . They both seem to provide a similar purpose. I have read a few comparisons between Where vs. Let but I am having trouble discerning when to use each. Could someone please provide some context or perhaps a few examples that demonstrate when to ...
What's the difference between getPath(), getAbsolutePath(), and getCanonicalPath() in Java?
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Consider these filenames:
C:\temp\file.txt - This is a path, an absolute path, and a canonical path.
.\file.txt - This is a path. It's neither an absolute path nor a canonical path.
C:\temp\myapp\bin\..\\..\file.txt - This is ...
Why should I not wrap every block in “try”-“catch”?
...an exception that you do not plan on handling in some way. You should consider how the application is going to systematically handle exceptions when you are designing it. This usually leads to having layers of error handling based on the abstractions - for example, you handle all SQL-related error...
Is it better to reuse a StringBuilder in a loop?
...ark.
public class ScratchPad {
static String a;
public static void main( String[] args ) throws Exception {
long time = System.currentTimeMillis();
for( int i = 0; i < 10000000; i++ ) {
StringBuilder sb = new StringBuilder();
sb.append( "someStri...