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How do I check two or more conditions in one ?
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If you are using JSP 2.0 and above It will come with the EL support:
so that you can write in plain english and use and with empty operators to write your test:
<c:if test="${(empty object_1.attribute_A) and (empty object_2.attribute_B)}">
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In Bash, how to add “Are you sure [Y/n]” to any command or alias?
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These are more compact and versatile forms of Hamish's answer. They handle any mixture of upper and lower case letters:
read -r -p "Are you sure? [y/N] " response
case "$response" in
[yY][eE][sS]|[yY])
do_something
;;
*)
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C++ performance vs. Java/C#
My understanding is that C/C++ produces native code to run on a particular machine architecture. Conversely, languages like Java and C# run on top of a virtual machine which abstracts away the native architecture. Logically it would seem impossible for Java or C# to match the speed of C++ because ...
How to build & install GLFW 3 and use it in a Linux project
...g time, about 3 hours in total, partly because I am unfamiliar with CMake, and partly because I am was unfamiliar with GLFW.
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Detect if device is iOS
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Detecting iOS
With iOS 13 iPad both User agent and platform strings are changed and differentiating between iPad and MacOS seems possible, so all answers below needs to take that into account now.
This might be the shortest alternative that also covers iOS 13:
function iO...
nginx missing sites-available directory
I installed Nginx on Centos 6 and I am trying to set up virtual hosts. The problem I am having is that I can't seem to find the /etc/nginx/sites-available directory.
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Why do function pointer definitions work with any number of ampersands '&' or asterisks '*'?
...foo)() = foo; works: foo is implicitly converted into a pointer to itself and that pointer is assigned to p1_foo.
The unary &, when applied to a function, yields a pointer to the function, just like it yields the address of an object when it is applied to an object. For pointers to ordinary f...
Hidden Features of Xcode 4
...r code to look as good as it runs, you've undoubtedly used #pragma mark - and #pragma mark <name> to provide a nice visual grouping in the Xcode class dropdown list. Xcode 4 now combines these into a single #pragma mark - <name>.
More on pragma mark.
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How can I check if a URL exists via PHP?
...t Found') {
$exists = false;
}
else {
$exists = true;
}
From here and right below the above post, there's a curl solution:
function url_exists($url) {
return curl_init($url) !== false;
}
share
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Android Studio Project Structure (v.s. Eclipse Project Structure)
I'm trying to learn android development and I am initially confused by the different project structures between Eclipse and Android Studio. This makes it difficult to follow tutorials designed for Eclipse. Could anyone let me know why these differences exist? Should they exist?
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