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Not equal != operator on NULL
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The only test for NULL is IS NULL or IS NOT NULL. Testing for equality is nonsensical because by definition one doesn't know what the value is.
Here is a wikipedia article to read:
https://en.wikipedia.org/wiki/Null_(SQL)
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Disable double-tap “zoom” option in browser on touch devices
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Doesn't work on latest iOS when double tapping an image.
– Adam Silver
Aug 3 at 15:49
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Creating the Singleton design pattern in PHP5
...] = new static;
}
return self::$instances[$cls];
}
}
Test code:
class Foo extends Singleton {}
class Bar extends Singleton {}
echo get_class(Foo::getInstance()) . "\n";
echo get_class(Bar::getInstance()) . "\n";
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How to send a header using a HTTP request through a curl call?
... --header parameter. example: curl --header "Accept: javascript" --header "test: hello" -v www.google.com
– Hatoru Hansou
Sep 24 '15 at 6:41
2
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cartesian product in pandas
..._, left), (_, right) in rows)
return df.reset_index(drop=True)
Quick test:
In [46]: a = pd.DataFrame(np.random.rand(5, 3), columns=["a", "b", "c"])
In [47]: b = pd.DataFrame(np.random.rand(5, 3), columns=["d", "e", "f"])
In [48]: cartesian(a,b)
Out[48]:
a b c...
How to programmatically set style attribute in a view
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Button b = new Button(this);
b.setBackgroundResource(R.drawable.selector_test);
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Difference between maven scope compile and provided for JAR packaging
...vides those classes. This
scope is only available on the compilation and test classpath, and is
not transitive.
Recap:
dependencies are not transitive (as you mentioned)
provided scope is only available on the compilation and test classpath, whereas compile scope is available in all clas...
Python: try statement in a single line
...oblem is that its actually a django model.objects.get query i am trying to test. the .get returns an error if no data is found... it doesn't return None (which annoys me)
– Brant
Mar 26 '10 at 16:36
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Rename package in Android Studio
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@Antonio drag the files in com.example.test to com.example and then delete com.example.test.
– Dick Lucas
Jul 28 '15 at 17:13
28
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Superscript in CSS only?
...xt.</p>
And your paragraph line height should not get screwed up.
Tested on IE7, IE8, FF3.6, SAFARI4, CHROME5, OPERA9
I tested using a p {line-height: 1.3;} (that is a good line height unless you want your lines to stick too close) and it still works, cause "-0.6em" is such a small amount ...