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How to check a not-defined variable in JavaScript
...ue for things that don't exist, undefined. The DOM returns null for almost all cases where it fails to find some structure in the document, but in JavaScript itself undefined is the value used.
Second, no, there is not a direct equivalent. If you really want to check for specifically for null, do:
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Django: Get model from string?
...d in 1.9) in favor of the the new application loading system.
-- Scott Woodall
Found it. It's defined here:
from django.db.models.loading import get_model
Defined as:
def get_model(self, app_label, model_name, seed_cache=True):
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jQuery Ajax File Upload
...ed. E.g. through FormData object, but unfortunately it is not supported by all/old browsers.
FormData support starts from following desktop browsers versions.
IE 10+
Firefox 4.0+
Chrome 7+
Safari 5+
Opera 12+
For more detail, see MDN link.
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How can I eliminate slow resolving/loading of localhost/virtualhost (a 2-3 second lag) on Mac OS X L
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I had the exact same problem and it was driving me crazy!
Put all your hosts file entries for localhost into one line like so:
127.0.0.1 localhost myproject.dev myotherproject.dev
::1 localhost
fe80::1%lo0 localhost
Worked like a charm for me. Seems like a bug in Lion.
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Firing a double click event from a WPF ListView item using MVVM
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Please, code behind is not a bad thing at all. Unfortunately, quite a lot people in the WPF community got this wrong.
MVVM is not a pattern to eliminate the code behind. It is to separate the view part (appearance, animations, etc.) from the logic part (workflow). F...
jQuery get mouse position within an element
...entOffset = $(this).parent().offset();
//or $(this).offset(); if you really just want the current element's offset
var relX = e.pageX - parentOffset.left;
var relY = e.pageY - parentOffset.top;
});
share
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Get local IP address
...sing Geraldo H Answer, but if anyone is using this, you may want to remove all ips that ends with 1, so it will remove loopback and virtualbox/vmware default ips
– Leonardo Xavier
Jun 23 '15 at 13:03
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JavaScript for detecting browser language preference [duplicate]
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I think the main problem here is that the browser settings don't actually affect the navigator.language property that is obtained via javascript.
What they do affect is the HTTP 'Accept-Language' header, but it appears this value is not available through javascript at all. (Probably why @and...
Safest way to convert float to integer in python?
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All integers that can be represented by floating point numbers have an exact representation. So you can safely use int on the result. Inexact representations occur only if you are trying to represent a rational number with a ...
How to do exponentiation in clojure?
...d recommend using this rather than going via Java interop since it handles all the Clojure arbitrary-precision number types correctly. It is in namespace clojure.math.numeric-tower.
It's called expt for exponentiation rather than power or pow which maybe explains why it's a bit hard to find ... any...