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What is the difference between include and require in Ruby?
My question is similar to " What is the difference between include and extend in Ruby? ".
11 Answers
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Context switches much slower in new linux kernels
We are looking to upgrade the OS on our servers from Ubuntu 10.04 LTS to Ubuntu 12.04 LTS. Unfortunately, it seems that the latency to run a thread that has become runnable has significantly increased from the 2.6 kernel to the 3.2 kernel. In fact the latency numbers we are getting are hard to belie...
In Python, how do I iterate over a dictionary in sorted key order?
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Haven't tested this very extensively, but works in Python 2.5.2.
>>> d = {"x":2, "h":15, "a":2222}
>>> it = iter(sorted(d.iteritems()))
>>> it.next()
('a', 2222)
>>> it.next()
('h', 15)
>>> it.next()
('x', 2)
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Git status shows files as changed even though contents are the same
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Update: as per the comment on this question, the problem has been solved:
That is easy: the first file has CRLF line-ends (windows), the second
LF (Unix). The file util (available in git\usr\bin) will show you that (file a b will reply
something like a: ASCII text, wit...
Is there an onSelect event or equivalent for HTML ?
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Here is the simplest way:
<select name="ab" onchange="if (this.selectedIndex) doSomething();">
<option value="-1">--</option>
<option value="1">option 1</option>
<option value="2">option 2</option>
<option v...
How to get an object's properties in JavaScript / jQuery?
In JavaScript / jQuery, if I alert some object, I get either [object] or [object Object]
7 Answers
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Select all child elements recursively in CSS
...x y matches every element y that is inside x, however deeply nested it may be - children, grandchildren and so on.
The asterisk * matches any element.
Official Specification: CSS 2.1: Chapter 5.5: Descendant Selectors
shar...
What is the best way to compare floats for almost-equality in Python?
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Python 3.5 adds the math.isclose and cmath.isclose functions as described in PEP 485.
If you're using an earlier version of Python, the equivalent function is given in the documentation.
def isclose(a, b, rel_tol=1e-09, abs_tol=0.0):
return abs(a-b) <= max(rel_tol * max(abs(a), abs(b))...
Why does (1 in [1,0] == True) evaluate to False?
...xpression is translated to
(1 in [1, 0]) and ([1, 0] == True)
which is obviously False.
This also happens for expressions like
a < b < c
which translate to
(a < b) and (b < c)
(without evaluating b twice).
See the Python language documentation for further details.
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