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if A vs if A is not None:
...if A:
will call A.__nonzero__() (see Special method names documentation) and use the return value of that function. Here's the summary:
object.__nonzero__(self)
Called to implement truth value testing and the built-in operation bool(); should return False or True, or their integer equival...
Ruby: How to get the first character of a string
...= "Smith"
first_name = "John"
Then you can get the initials very cleanly and readably:
puts first_name.initial # prints J
puts last_name.initial # prints S
The other method mentioned here doesn't work on Ruby 1.8 (not that you should be using 1.8 anymore anyway!--but when this answer was p...
Creating a new dictionary in Python
...
Is there any difference between dict() and {}? Or do people just prefer one over the other?
– Matt
Mar 2 '12 at 17:13
53
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Limit labels number on Chart.js line chart
...i missing some place where i may actually find all those little properties and overridable callbacks documented?
– Max Yari
Mar 9 '18 at 16:28
1
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Tool to Unminify / Decompress JavaScript [closed]
Are there any command line scripts and/or online tools that can reverse the effects of minification similar to how Tidy can clean up horrific HTML?
...
Converting a string to a date in JavaScript
...ormat" doesn't work reliably by itself. String are sometimes parsed as UTC and sometimes as localtime (based on browser vendor and version). The best practice should always be to store dates as UTC and make computations as UTC.
To parse a date as UTC, append a Z - e.g.: new Date('2011-04-11T10:20:3...
Ruby: What is the easiest way to remove the first element from an array?
...
Note this mutates the array and returns nil on an empty array. See drop for an alternative, as mentioned in the other answer.
– Jay
Oct 15 '15 at 21:37
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How to convert SSH keypairs generated using PuTTYgen (Windows) into key-pairs used by ssh-agent and
I've generated key pairs using PuTTYgen and been logging in using Pageant, so that I have to enter my pass-phrase only once when my system boots.
...
How to check if an object is an array?
...Array.isArray(obj)
(Supported by Chrome 5, Firefox 4.0, IE 9, Opera 10.5 and Safari 5)
For backward compatibility you can add the following
# only implement if no native implementation is available
if (typeof Array.isArray === 'undefined') {
Array.isArray = function(obj) {
return Object.pr...
How to sum up an array of integers in C#
...
Provided that you can use .NET 3.5 (or newer) and LINQ, try
int sum = arr.Sum();
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