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javascript set a variable if undefined
... x === 'undefined') ? your_default_value : x;
On newer browsers it's actually safe to write:
var x = (x === undefined) ? your_default_value : x;
but be aware that it is possible to subvert this on older browsers where it was permitted to declare a variable named undefined that has a defined val...
How to cherry pick a range of commits and merge into another branch?
...ue".
or skip this patch, and instead run "git rebase --skip"
or cancel the all thing with a "git rebase --abort" (and put back the integration branch on the tmp branch)
After that rebase --onto, integration will be back at the last commit of the integration branch (that is "tmp" branch + all the re...
How can I sanitize user input with PHP?
Is there a catchall function somewhere that works well for sanitizing user input for SQL injection and XSS attacks, while still allowing certain types of HTML tags?
...
What are the differences between vector and list data types in R?
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Technically lists are vectors, although very few would use that term. "list" is one of several modes, with others being "logical", "character", "numeric", "integer". What you are calling vectors are "atomic vectors" in strict R parl...
How do I check OS with a preprocessor directive?
...Unix (Linux, *BSD, Mac OS X)
See this related question on some of the pitfalls of using this check.
unix
__unix
__unix__
Mac OS X
__APPLE__
__MACH__
Both are defined; checking for either should work.
Linux
__linux__
linux Obsolete (not POSIX compliant)
__linux Obsolete (not POSIX compliant)
...
Utilizing the GPU with c# [closed]
...OpenTK -- dead/Cloo) - many of these are just bindings - ie enable you to call the GPU from C#, but your kernel code (code which is actually run on the GPU) needs to be written in C or OpenCL, meaning you must use (and learn) another language.
As I said, I would recommend Cudafy over all the other...
Getting a list of files in a directory with a glob
...ing operations for you. The functions and types are declared in a header called glob.h, so you'll need to #include it. If open up a terminal an open the man page for glob by typing man 3 glob you'll get all of the information you need to know to use the functions.
Below is an example of how you c...
'console' is undefined error for Internet Explorer
...onsole = ...
An undefined variable cannot be referred directly. However, all global variables are attributes of the same name of the global context (window in case of browsers), and accessing an undefined attribute is fine.
Or use if (typeof console === 'undefined') console = ... if you want to a...
How do I add multiple arguments to my custom template filter in a django template?
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It is possible and fairly simple.
Django only allows one argument to your filter, but there's no reason you can't put all your arguments into a single string using a comma to separate them.
So for example, if you want a filter that checks if variable X is in the list [1...
How can I programmatically check whether a keyboard is present in iOS app?
... responder. I have a view controller with multiple child view controllers, all of which contain UITextFields. Using this method, i cannot tell from my parent view controller whether the keyboard is shown. The only reliable way is to use the notification method explained in the other answers
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