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What's the difference between window.location and document.location in JavaScript?
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+1 but also see the answers by Phil Hamer and Christoph below, they add essential background info and caveats to fully understand the issue.
– Jon z
Oct 31 '14 at 19:12
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What is the difference between a mutable and immutable string in C#?
What is the difference between a mutable and immutable string in C#?
15 Answers
15
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Does the ternary operator exist in R?
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As if is function in R and returns the latest evaluation, if-else is equivalent to ?:.
> a <- 1
> x <- if(a==1) 1 else 2
> x
[1] 1
> x <- if(a==2) 1 else 2
> x
[1] 2
The power of R is vectorization. The vectorization of t...
How to test if one java class extends another at runtime?
...e will return true if the class/instance is a member of the type hierarchy and are not restrictive to direct superclass/subclass relationships. For example:
// if A.class extends B.class, and B.class extends C.class
C.class.isAssignableFrom(A.class); // evaluates to true
// ...and...
new A() instan...
Clean ways to write multiple 'for' loops
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}
(or just:
for ( auto& elem: m ) {
}
if you have C++11.)
And if you need the three indexes during such iterations, it's
possible to create an iterator which exposes them:
class Matrix3D
{
// ...
class iterator : private std::vector<int>::iterator
{
Matri...
How do I get user IP address in django?
...tem (e.g., in the case of Heroku: Get client's real IP address on Heroku)
And then just pass the request as argument to it;
get_client_ip(request)
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Creating an empty file in Ruby: “touch” equivalent?
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FileUtils.touch looks like what it does, and mirrors* the touch command:
require 'fileutils'
FileUtils.touch('file.txt')
* Unlike touch(1) you can't update mtime or atime alone. It's also missing a few other nice options.
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Split string on the first white space occurrence
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If you only care about the space character (and not tabs or other whitespace characters) and only care about everything before the first space and everything after the first space, you can do it without a regular expression like this:
str.substr(0,str.indexOf(' ')); /...
How to reference constants in EL?
...e.YourConstants" %>
This will under the covers be imported via ImportHandler#importClass() and be available as ${YourConstants.FOO}.
Note that all java.lang.* classes are already implicitly imported and available like so ${Boolean.TRUE} and ${Integer.MAX_VALUE}. This only requires a more recen...
Refreshing OAuth token using Retrofit without modifying all calls
We are using Retrofit in our Android app, to communicate with an OAuth2 secured server. Everything works great, we use the RequestInterceptor to include the access token with each call.
However there will be times, when the access token will expire, and the token needs to be refreshed. When the toke...