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Check for array not empty: any?
...something or not. This includes things that evaluate to false, such as nil and false.
>> a = []
=> []
>> a.empty?
=> true
>> a = [nil, false]
=> [nil, false]
>> a.empty?
=> false
>> a = [nil]
=> [nil]
>> a.empty?
=> false
The method any? comes ...
What is the meaning of “$” sign in JavaScript
...from one of the popular JavaScript libraries (jQuery, ProtoType, mooTools, and so on).
There's nothing mysterious about the use of $ in JavaScript. $ is simply a valid JavaScript identifier.
JavaScript allows upper and lower letters, numbers, and $ and _. The $ was intended to be used for machine-...
Rails create or update magic?
...
Rails 6
Rails 6 added an upsert and upsert_all methods that deliver this functionality.
Model.upsert(column_name: value)
[upsert] It does not instantiate any models nor does it trigger Active Record callbacks or validations.
Rails 5, 4, and 3
Not ...
How do I check if file exists in Makefile so I can delete it?
...
Helps to also understand what $(wildcard pattern) actually does. See link.
– Dr. Dan
Nov 5 '18 at 22:43
1
...
How to make code wait while calling asynchronous calls like Ajax [duplicate]
...me propreitory framework..there is load function where page starts loading and before page loads i need to get data and only function i can override is load function...
– thecodejack
Dec 26 '12 at 8:15
...
Matplotlib make tick labels font size smaller
...overflow.com/a/11386056/42346
The code below is for illustrative purposes and may not necessarily be optimized.
import matplotlib.pyplot as plt
import numpy as np
def xticklabels_example():
fig = plt.figure()
x = np.arange(20)
y1 = np.cos(x)
y2 = (x**2)
y3 = (x**3)
yn = ...
How do I undo a checkout in git?
...to/file
For the entire repository working copy:
git reset --hard HEAD
And if that doesn't work, then you can look in the reflog to find your old head SHA and reset to that:
git reflog
git reset --hard <sha from reflog>
HEAD is a name that always points to the latest commit in your curr...
Remove excess whitespace from within a string
...tring from a database query, then I remove all HTML tags, carriage returns and newlines before I put it in a CSV file. Only thing is, I can't find a way to remove the excess white space from between the strings.
...
How can I use Google's Roboto font on a website?
I want to use Google's Roboto font on my website and I am following this tutorial:
13 Answers
...
Command not found error in Bash variable assignment
...d your '=' sign.
When you write:
STR = "foo"
bash tries to run a command named STR with 2 arguments (the strings '=' and 'foo')
When you write:
STR =foo
bash tries to run a command named STR with 1 argument (the string '=foo')
When you write:
STR= foo
bash tries to run the command foo ...