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Detect if an input has text in it using CSS — on a page I am visiting and do not control?
... script will work in Chrome, or Firefox with Greasemonkey or Scriptish installed, or in any browser that supports userscripts (i.e. most browsers, except IE).
See a demo of the limits of CSS plus the javascript solution at this jsBin page.
// ==UserScript==
// @name _Dynamically style inputs b...
Extracting specific columns from a data frame
...
Using the dplyr package, if your data.frame is called df1:
library(dplyr)
df1 %>%
select(A, B, E)
This can also be written without the %>% pipe as:
select(df1, A, B, E)
share
...
Make an existing Git branch track a remote branch?
... 1.7.0 (before 1.8.0):
git branch --set-upstream foo upstream/foo
Notes:
All of the above commands will cause local branch foo to track remote branch foo from remote upstream.
The old (1.7.x) syntax is deprecated in favor of the new (1.8+) syntax. The new syntax is intended to be more intuitive a...
Rule-of-Three becomes Rule-of-Five with C++11?
...(T&& other) as Philipp points out in his answer, if it has dynamically allocated members, or generally stores pointers. Just like you should have a copy-ctor, assignment operator and destructor if the points mentioned before apply.
Thoughts?
...
What is the difference between `new Object()` and object literal notation?
...rly recognizable as to what is happening, so using new Object(), you are really just typing more and (in theory, if not optimized out by the JavaScript engine) doing an unnecessary function call.
These
person = new Object() /*You should put a semicolon here too.
It's not required, but it is goo...
Capitalize words in string [duplicate]
...{string} str String to be modified
* @param {boolean=false} lower Whether all other letters should be lowercased
* @return {string}
* @usage
* capitalize('fix this string'); // -> 'Fix This String'
* capitalize('javaSCrIPT'); // -> 'JavaSCrIPT'
* capitalize('javaSCrIPT...
Why does CSS not support negative padding?
...
sometimes it's not practical to edit the CSS of all children of a container. You might have generic CSS that applies to these elements across the document, and you don't want to change it for the contents of a particular container, for example.
– Rolf...
HashSet vs LinkedHashSet
...ax(2*c.size(), 11), .75f, true); // <-- boolean dummy argument
addAll(c);
}
And (one example of) a HashSet constructor that takes a boolean argument is described, and looks like this:
/**
* Constructs a new, empty linked hash set. (This package private
* constructor is only used by Li...
Using ZXing to create an Android barcode scanning app [duplicate]
...de reader application which — via Android's intent mechanism — can be called by other applications who wish to integrate barcode scanning.
The easiest way to do this is to call the ZXing SCAN Intent from your application, like this:
public Button.OnClickListener mScan = new Button.OnClickListe...
Twitter Bootstrap: Text in navbar
According to the twitter bootstrap documentation , I should be able to "Wrap strings of text in a <p> tag for proper leading and color." When I do this, at any level under navbar it simply doesn't inherit any of the navbar classes. Wrapping the string in <a> tags renders it but ...