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Define preprocessor macro through CMake?
... From the linked page: "Note This command has been superseded by alternatives: Use add_compile_definitions() to add preprocessor definitions." Maybe this answer needs an edit?
– M.Herzkamp
Jul 10 '18 at 9:01
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Checking if an Android application is running in the background
...vityVisible;
}
Register your application class in AndroidManifest.xml:
<application
android:name="your.app.package.MyApplication"
android:icon="@drawable/icon"
android:label="@string/app_name" >
Add onPause and onResume to every Activity in the project (you may create a common...
Best way to detect when a user leaves a web page?
...ack if the user really wants to leave. See the demo onbeforeunload Demo.
Alternatively, you can send out an Ajax request when he leaves.
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Is a URL allowed to contain a space?
... be encoded, is + just a commonly followed convention, or a legitimate alternative?
10 Answers
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PHP - How to check if a string contains a specific text [duplicate]
...trings are falsey, so you can just write:
if ($a) {
echo 'text';
}
Although if you're asking if a particular substring exists in that string, you can use strpos() to do that:
if (strpos($a, 'some text') !== false) {
echo 'text';
}
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Check if a number is int or float
...not, it works for both Python 2 and Python 3.
import sys
if sys.version < '3':
integer_types = (int, long,)
else:
integer_types = (int,)
isinstance(yourNumber, integer_types) # returns True if it's an integer
isinstance(yourNumber, float) # returns True if it's a float
Notice that ...
check if a std::vector contains a certain object? [duplicate]
Is there something in <algorithm> which allows you to check if a std:: container contains something? Or, a way to make one, for example:
...
How to name variables on the fly?
...because that number would be a convenient way to access them later.
orca <- list()
orca[1] <- "Hi"
orca[2] <- 59
Otherwise, assign is just what you want.
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Verifying that a string contains only letters in C#
...
bool result = input.All(Char.IsLetter);
bool result = input.All(Char.IsLetterOrDigit);
bool result = input.All(c=>Char.IsLetterOrDigit(c) || c=='_');
sh...
Why does NULL = NULL evaluate to false in SQL server
...ve (NaN == NaN) == false && (NaN != Nan) == false && (NaN < NaN) == false && ... - because, well, if it's not a number, you just can't say much about it; it's something unknown. The concept is sound, even if unintuitive to people who have never seen it before.
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