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Check a collection size with JSTL
...r Facelets:
<... xmlns:fn="http://java.sun.com/jsp/jstl/functions">
And use like this in your page:
<p>The length of the companies collection is: ${fn:length(companies)}</p>
So to test with length of a collection:
<c:if test="${fn:length(companies) gt 0}">
</c:if>
A...
Why does scanf() need “%lf” for doubles, when printf() is okay with just “%f”?
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Since С99 the matching between format specifiers and floating-point argument types in C is consistent between printf and scanf. It is
%f for float
%lf for double
%Lf for long double
It just so happens that when arguments of type float are passed as variadic parameters,...
I want to delete all bin and obj folders to force all projects to rebuild everything
I work with multiple projects, and I want to recursively delete all folders with the name 'bin' or 'obj' that way I am sure that all projects will rebuild everything (sometimes it's the only way to force Visual Studio to forget all about previous builds).
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Ruby: kind_of? vs. instance_of? vs. is_a?
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kind_of? and is_a? are synonymous.
instance_of? is different from the other two in that it only returns true if the object is an instance of that exact class, not a subclass.
Example:
"hello".is_a? Object and "hello".kind_of? Obje...
How do I declare a global variable in VBA?
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When I try to declare an array as public it says: array and user-defined data types can't be declared as public.
– kapilddit
Nov 13 '19 at 12:25
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What's the best way to convert a number to a string in JavaScript? [closed]
...he only conceivable: the number does not care nor know how it was entered, and the standard printed representation is with exactly one digit before the dot.
– Svante
Sep 2 '15 at 18:32
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Big O, how do you calculate/approximate it?
Most people with a degree in CS will certainly know what Big O stands for .
It helps us to measure how well an algorithm scales.
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Object reference not set to an instance of an object.Why doesn't .NET show which object is `null`?
Regarding this .NET unhandled exception message:
5 Answers
5
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Using Emacs as an IDE
...o two, the bottom being a shell which I use to type in compile or make commands, and the top is often some sort of documentation or README file that I want to consult while I am working. Now I know there are some pretty expert Emacs users out there, and I am curious what other Emacs functionally is...
What is an Intent in Android?
... happen. Depending on the intent, apps or the OS might be listening for it and will react accordingly. Think of it as a blast email to a bunch of friends, in which you tell your friend John to do something, or to friends who can do X ("intent filters"), to do X. The other folks will ignore the email...