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MongoDB relationships: embed or reference?
...m a relational database background. I want to design a question structure with some comments, but I don't know which relationship to use for comments: embed or reference ?
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Easiest way to convert int to string in C++
... each numeric type) and std::to_string, the counterparts of the C atoi and itoa but expressed in term of std::string.
#include <string>
std::string s = std::to_string(42);
is therefore the shortest way I can think of. You can even omit naming the type, using the auto keyword:
auto s = st...
What's the difference between a proc and a lambda in Ruby?
...g lambda {} gives you a proc that checks the number of arguments passed to it. From ri Kernel#lambda:
Equivalent to Proc.new, except the resulting Proc objects check the number of parameters passed when called.
An example:
p = Proc.new {|a, b| puts a**2+b**2 } # => #<Proc:0x3c7d28@(irb)...
echo that outputs to stderr
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You could do this, which facilitates reading:
>&2 echo "error"
>&2 copies file descriptor #2 to file descriptor #1. Therefore, after this redirection is performed, both file descriptors will refer to the same file: the one file descriptor...
Cannot set some HTTP headers when using System.Net.WebRequest
...right to the last section of the answer.
If you want to know better, read it all, and i hope you'll enjoy...
I countered this problem too today, and what i discovered today is that:
the above answers are true, as:
1.1 it's telling you that the header you are trying to add already exist and yo...
Editing dictionary values in a foreach loop
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Setting a value in a dictionary updates its internal "version number" - which invalidates the iterator, and any iterator associated with the keys or values collection.
I do see your point, but at the same time it would be odd if the values collection could change ...
Running SSH Agent when starting Git Bash on Windows
I am using git bash. I have to use
8 Answers
8
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How do I implement basic “Long Polling”?
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It's simpler than I initially thought.. Basically you have a page that does nothing, until the data you want to send is available (say, a new message arrives).
Here is a really basic example, which sends a simple string afte...
Static/Dynamic vs Strong/Weak
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Static/Dynamic Typing is about when type information is acquired (Either at compile time or at runtime)
Strong/Weak Typing is about how strictly types are distinguished (e.g. whether the language tries to do an implicit conversion from strings to numbers).
See the wiki-page for more detail...
How to have jQuery restrict file types on upload?
I would like to have jQuery limit a file upload field to only jpg/jpeg, png, and gif. I am doing backend checking with PHP already. I am running my submit button through a JavaScript function already so I really just need to know how to check for the file types before submit or alert.
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