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What is the difference between a var and val definition in Scala?
...ge the state of that object. At the root of it, however, there was a var.
Now, immutability is a good thing for many reasons. First, if an object doesn't change internal state, you don't have to worry if some other part of your code is changing it. For example:
x = new B(0)
f(x)
if (x.value.value ...
How to convert R Markdown to PDF?
...
Updated Answer (10 Feb 2013)
rmarkdown package:
There is now an rmarkdown package available on github that interfaces with Pandoc.
It includes a render function. The documentation makes it pretty clear how to convert rmarkdown to pdf among a range of other formats. This includes i...
What are the barriers to understanding pointers and what can be done to overcome them? [closed]
...implified. There's more overhead and a lot more details you would
need to know if you need to deal with memory on a low-level basis. However, for the
intents of explaining memory and pointers, it is accurate enough.
Let's assume the THouse class used below looks like this:
type
THouse = clas...
Get last record in a queryset
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2017 and the accepted answers is out of date now. As shown below you should use queryset.last().
– wobbily_col
Jul 14 '17 at 14:02
add a comment
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Getting the client's timezone offset in JavaScript
...ndard since ES 1, so I'm sure any implementation problem might be fixed by now, I mean, that is a 7 years old article.
– LasagnaAndroid
May 30 '14 at 20:24
54
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Is there a difference between “throw” and “throw ex”?
...link isn't being forwarded correctly after a blog migration. Looks like it now lives here. Edit: Hey, wait, that's your blog! Fix your own links! ;^D
– ruffin
Oct 8 '19 at 21:21
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How do I design a class in Python?
...ant the first footstep of a dog, you do something like:
dog.footstep(0)
Now, it may be that for your case you need to read in your raw data file and compute the footstep locations. All this could be hidden in the footstep() function so that it only happens once. Something like:
class Dog:
de...
Why does document.querySelectorAll return a StaticNodeList rather than a real Array?
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I don't know why it returns a node list instead of an array, maybe because like getElementsByTagName it will update the result when you update the DOM. Anyway a very simple method to transform that result in a simple array is:
Array....
What is a difference between
... arrays are what we call reifiable types. This means that at runtime Java knows that this array was actually instantiated as an array of integers which simply happens to be accessed through a reference of type Number[].
So, as you can see, one thing is the actual type of the object, and another thin...
How to create the perfect OOP application [closed]
... p contains (np/100 rounded up to the nearest 0.05) amount of sales tax.
Now, what are the relationships between all those nouns?
Basic Sales Tax is a kind of Sales Tax
Import Duty is a kind of Sales Tax
A Sales Tax has a Rate which is a Decimal
Books are a kind of Item
Food is a kind of Item
Me...