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How to check if object has any properties in JavaScript?
...ave any way to create non-enumerable properties.
However this has changed now with ECMAScript 5th Edition, and we are able to create non-enumerable, non-writable or non-deletable properties, so the above method can fail, e.g.:
var obj = {};
Object.defineProperty(obj, 'test', { value: 'testVal',
...
Android 4.1: How to check notifications are disabled for the application?
...d for the new notifications declares that you can't.
Edit
2016 update: Now you can check it, as said in this Google I/O 2016 video.
Use NotificationManagerCompat.areNotificationsEnabled(), from support library, to check if notifications are blocked on API 19+. The versions below API 19 will ret...
Node.js app can't run on port 80 even though there's no other process blocking the port
... Not sure why, but on Ubuntu 14.04 this did not work for me. I now use port forwarding via ssh, which is just as easy. I posted an answer below.
– panepeter
Feb 27 '18 at 9:12
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Statistics: combinations in Python
... N and K due to floating point precision. But we can fix that - see above, now it should not err for big numbers
– Nas Banov
Sep 17 '13 at 1:17
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Why can't I reference my class library?
...e to our current 4.0 requirement, I downgraded the new solution to 4.0 and now my other project has no problems building against it. +1 for helping me stay sane!
– David Peterson
Nov 27 '12 at 22:57
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changing source on html5 video tag
...tag, but it would always generate a failure on a javascript debug console. Now I know I can hold off on adding a 'source' until the user selects one. Till now, I didn't understand I needed to make the use CreateElement() to make a source, and then use appendChild() to add it to the video element! Fo...
typeof !== “undefined” vs. != null
...e would use the !== or === operators when comparing a value whose type is known to be a string.
– Nicolas Rinaudo
Aug 30 '13 at 7:38
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Tab key == 4 spaces and auto-indent after curly braces in Vim
...As has been pointed out in a couple of answers below, the preferred method now is NOT to use smartindent, but instead use the following (in your .vimrc):
filetype plugin indent on
" show existing tab with 4 spaces width
set tabstop=4
" when indenting with '>', use 4 spaces width
set shiftwidth=4...
How to use concerns in Rails 4
The default Rails 4 project generator now creates the directory "concerns" under controllers and models. I have found some explanations about how to use routing concerns, but nothing about controllers or models.
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Styling HTML email for Gmail
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They now do media queries too and fuller support for css styling. stackoverflow.com/questions/39759764/…
– crowmagnumb
Sep 30 '16 at 15:44
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