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Check if inputs are empty using jQuery
I have a form that I would like all fields to be filled in. If a field is clicked into and then not filled out, I would like to display a red background.
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Get type of all variables
...(c(TRUE, FALSE)) #a vector containing only logicals: logical
#R is really cramping my style, killing my high, irritation is increasing:
typeof(factor()) #an empty factor has default type: integer
typeof(factor(3.14)) #a factor containing doubles: integer
typeof(factor(...
How to avoid scientific notation for large numbers in JavaScript?
... and browsers based on it (Chrome, the new Edge [v79+], Brave) and Firefox all have support; Safari's support is underway.
Here's how you'd use BigInt for it: BigInt(n).toString()
Example:
const n = 13523563246234613317632;
console.log("toFixed (wrong): " + n.toFixed());
console.log("BigInt...
How to run two jQuery animations simultaneously?
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I believe I found the solution in the jQuery documentation:
Animates all paragraph to a left style
of 50 and opacity of 1 (opaque,
visible), completing the animation
within 500 milliseconds. It also will
do it outside the queue, meaning it
will automatically start without
waiting f...
How to search for a string in text files?
... if 'blabla' in f.read():
print("true")
Another trick: you can alleviate the possible memory problems by using mmap.mmap() to create a "string-like" object that uses the underlying file (instead of reading the whole file in memory):
import mmap
with open('example.txt') as f:
s = mm...
How can I get the iOS 7 default blue color programmatically?
... Yes, definitely not a good idea to hard-code any value that could potentially change. Especially when there is an API to query the actual value.
– Nicolas Miari
Oct 2 '15 at 2:49
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android webview geolocation
...nts WebChromeClient.onGeolocationPermissionsShowPrompt(). This method
is called by the WebView to obtain permission to disclose the user's location to JavaScript. (In the case of the browser, we show a prompt to the user.) The default implementation does nothing, so permission is never obtained and...
JS: iterating over result of getElementsByClassName using Array.forEach
...on (in modern browsers, at least. Older browsers returned a NodeList).
In all modern browsers (pretty much anything other IE <= 8), you can call Array's forEach method, passing it the list of elements (be it HTMLCollection or NodeList) as the this value:
var els = document.getElementsByClassNam...
How to echo shell commands as they are executed
In a shell script, how do I echo all shell commands called and expand any variable names?
13 Answers
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Can Java 8 code be compiled to run on Java 7 JVM?
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No, I don't think it will. Java has a small share of the desktop market, but keeps that little share in a pretty tight grip. But it does hamper the adoption of new versions and features. I will not be able to use Java 8 features in the code I write for quite some t...