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How can I suppress all output from a command using Bash?
...sn't any option for this program to be quiet. How can I prevent the script from displaying anything?
7 Answers
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How do I make and use a Queue in Objective-C?
...ay (QueueAdditions)
// Queues are first-in-first-out, so we remove objects from the head
- (id) dequeue {
// if ([self count] == 0) return nil; // to avoid raising exception (Quinn)
id headObject = [self objectAtIndex:0];
if (headObject != nil) {
[[headObject retain] autorelease]...
How do I remove the old history from a git repository?
...
Quoted from the linked wiki page on grafts. "As of Git 1.6.5, the more flexible git replace has been added, which allows you to replace any object with any other object, and tracks the associations via refs which can be pushed and p...
Difference between wait() and sleep()
...l sleep on Thread.
Yet another point is that you can get spurious wakeups from wait (i.e. the thread which is waiting resumes for no apparent reason). You should always wait whilst spinning on some condition as follows:
synchronized {
while (!condition) { mon.wait(); }
}
...
What is the difference between quiet NaN and signaling NaN?
I have read about floating-point and I understand that NaN could result from operations. But I can't understand what these are concepts exactly. What is the difference between them?
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Why does calling a method in my derived class call the base class method?
...tion. You cannot create instances of abstract classes, but you can inherit from them and create instances of your inherited classes and access them using the base class definition. In your example this would look like:
public abstract class Person
{
public abstract void ShowInfo();
}
public cl...
Load multiple packages at once
...dplyr, psych, tm)
and if the package is missing p_load will download it from CRAN or Bioconductor.
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Can C++ code be valid in both C++03 and C++11 but do different things?
... right-shift in C++03. This is more likely to break existing code though: (from http://gustedt.wordpress.com/2013/12/15/a-disimprovement-observed-from-the-outside-right-angle-brackets/)
template< unsigned len > unsigned int fun(unsigned int x);
typedef unsigned int (*fun_t)(unsigned int);
temp...
SVN how to resolve new tree conflicts when file is added on two branches
...der version (2009) of the "Tree Conflict" design document:
XFAIL conflict from merge of add over versioned file
This test does a merge which brings a file addition without history onto an
existing versioned file.
This should be a tree conflict on the file of the 'local obstruction, incoming add upo...
How can I do a line break (line continuation) in Python?
...== True and \
b == False
Check the style guide for more information.
From your example line:
a = '1' + '2' + '3' + \
'4' + '5'
Or:
a = ('1' + '2' + '3' +
'4' + '5')
Note that the style guide says that using the implicit continuation with parentheses is preferred, but in this part...