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What is the difference between ${var}, “$var”, and “${var}” in the Bash shell?
...bar', so loop runs once and
done # prints nothing (actually "")
var="foo bar"
for i in "${var}bar"; do # Expands to 'for i in "foo barbar"; do...'
echo $i # so runs the loop once
done
# foo barbar
Note that "${var}bar" in the second example above could also ...
Ruby: require vs require_relative - best practice to workaround running in both Ruby =1.
...ernel
def require_relative(path)
require File.join(File.dirname(caller[0]), path.to_str)
end
end
end
This allows you to use require_relative as you would in ruby 1.9.2 in ruby 1.8 and 1.9.1.
share
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How to extract img src, title and alt from html using php? [duplicate]
I would like to create a page where all images which reside on my website are listed with title and alternative representation.
...
What's the difference between eval, exec, and compile?
...
The short answer, or TL;DR
Basically, eval is used to evaluate a single dynamically generated Python expression, and exec is used to execute dynamically generated Python code only for its side effects.
eval and exec have these two differences:
eval accep...
Passing arguments to “make run”
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What's a macro? Isn't that what people call environment variables? What's the difference between a macro and an environment variable?
– KcFnMi
Aug 12 at 23:05
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How to sort Map values by key in Java?
...he demonstration, but doesn't have to be a lambda expression
Comparator<Foo> comparator = (Foo o1, Foo o2) -> {
...
}
SortedSet<Foo> keys = new TreeSet<>(comparator);
keys.addAll(map.keySet());
Remember when using a TreeMap or TreeSet that it will have different p...
PHP array_filter with arguments
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As an alternative to @Charles's solution using closures, you can actually find an example in the comments on the documentation page. The idea is that you create an object with the desired state ($num) and the callback method (taking $i as an argument):
class LowerThanFilter {
private ...
django - why is the request.POST object immutable?
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It's a bit of a mystery, isn't it? Several superficially plausible theories turn out to be wrong on investigation:
So that the POST object doesn't have to implement mutation methods? No: the POST object belongs to the django.http.QueryDict class, which implements a full set ...
Servlet for serving static content
...;url-pattern>/</url-pattern>
</servlet-mapping>
This basically just maps all content files by extension to the default servlet, and everything else to "myAppServlet".
It works in both Jetty and Tomcat.
s...
Binding an enum to a WinForms combo box, and then setting it
...dView.CurrentRow.Cells["comboColumnCell"].Value. I can see value but internally it throws null pointer exception
– ssal
Jun 5 '14 at 17:18
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