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Why would I ever use push_back instead of emplace_back?
C++11 vectors have the new function emplace_back . Unlike push_back , which relies on compiler optimizations to avoid copies, emplace_back uses perfect forwarding to send the arguments directly to the constructor to create an object in-place. It seems to me that emplace_back does everything p...
How do I get a substring of a string in Python?
Is there a way to substring a string in Python, to get a new string from the third character to the end of the string?
13 A...
Default behavior of “git push” without a branch specified
I use the following command to push to my remote branch:
12 Answers
12
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How to get current foreground activity context in android?
Whenever my broadcast is executed I want to show alert to foreground activity.
14 Answers
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How to read a large file - line by line?
I want to iterate over each line of an entire file. One way to do this is by reading the entire file, saving it to a list, then going over the line of interest. This method uses a lot of memory, so I am looking for an alternative.
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Create a tar.xz in one command
I am trying to create a .tar.xz compressed archive in one command. What is the specific syntax for that?
5 Answers
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How to organize large R programs?
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The standard answer is to use packages -- see the Writing R Extensions manual as well as different tutorials on the web.
It gives you
a quasi-automatic way to organize your code by topic
strongly encourages you to write a help file, making you ...
Can you explain the concept of streams?
...quence of bytes. Each stream provides means for reading and writing bytes to its given backing store. But what is the point of the stream? Why isn't the backing store itself what we interact with?
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Where do I use delegates? [closed]
...the example from the link, you will notice that Array.Find takes the array to search and then a predicate to handle the criteria of what to find. In this case it passes a method ProductGT10 which matches the Predicate signature.
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What exactly does Perl's “bless” do?
...Class";
Now when you invoke a method on $object, Perl know which package to search for the method.
If the second argument is omitted, as in your example, the current package/class is used.
For the sake of clarity, your example might be written as follows:
sub new {
my $class = shift;
my $...