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Is there a standard function to check for null, undefined, or blank variables in JavaScript?
...re a universal JavaScript function that checks that a variable has a value and ensures that it's not undefined or null ? I've got this code, but I'm not sure if it covers all cases:
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Customizing the template within a Directive
...in order for the form's controller to recognize its newly formed existence and include it in validation. I could not get it to work in a directive's compile property.
– m.e.conroy
Mar 24 '14 at 15:08
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function declaration isn't a prototype
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In C int foo() and int foo(void) are different functions. int foo() accepts an arbitrary number of arguments, while int foo(void) accepts 0 arguments. In C++ they mean the same thing. I suggest that you use void consistently when you mean n...
Painless way to install a new version of R?
Andrew Gelman recently lamented the lack of an easy upgrade process for R (probably more relevant on Windows than Linux). Does anyone have a good trick for doing the upgrade, from installing the software to copying all the settings/packages over?
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Detect Safari using jQuery
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Using a mix of feature detection and Useragent string:
var is_opera = !!window.opera || navigator.userAgent.indexOf(' OPR/') >= 0;
var is_Edge = navigator.userAgent.indexOf("Edge") > -1;
var is_chrome = !!window.chrome && !is_opera...
What is the difference between a Docker image and a container?
...en using Docker, we start with a base image. We boot it up, create changes and those changes are saved in layers forming another image.
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'Specified condition “$(PackageAsSingleFile)” evaluates to “” instead of a boolean?
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mucking with the web deploy settings caused this for me, and restarting VS was also the fix.
– CodeGrue
Apr 9 '13 at 18:32
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Git repository broken after computer died
My computer went dead and now one of my git repositories is broken. When I try to checkout master it tells me:
15 Answers
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Advantage of switch over if-else statement
...0 have an expected action (that presently is the same action). Performance and space need to be considered but are not critical. I've abstracted the snippet so don't hate me for the naming conventions.
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Most efficient way to concatenate strings in JavaScript?
In JavaScript, I have a loop that has many iterations, and in each iteration, I am creating a huge string with many += operators. Is there a more efficient way to create a string? I was thinking about creating a dynamic array where I keep adding strings to it and then do a join. Can anyone explain...