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How can I add to List
...ranteed to read the values of specific type T if I read from the list.
So now, thanks to generics wildcards, I can do any of these calls with that single method:
// copy(dest, src)
Collections.copy(new ArrayList<Number>(), new ArrayList<Number());
Collections.copy(new ArrayList<Number&...
What is a coroutine?
...
And: Cooperative multitasking, also known as non-preemptive multitasking, is a style of computer multitasking in which the operating system never initiates a context switch from a running process to another process. Instead, processes voluntarily yield control p...
CSS content property: is it possible to insert HTML instead of Text?
...; tags, this won't work in pseudo-elements (at least as of today, I don't know if it is specified anywhere that it shouldn't, so it may be a not-yet implemented feature).
Now, a small demo of some html markup in a pseudo element :
/*
** original svg code :
*
*<svg width="200" height=...
How do you write a migration to rename an ActiveRecord model and its table in Rails?
...y.
Edit:
In Rails 3.1 & 4, ActiveRecord::Migration::CommandRecorder knows how to reverse rename_table migrations, so you can do this:
class RenameOldTableToNewTable < ActiveRecord::Migration
def change
rename_table :old_table_name, :new_table_name
end
end
(You still have to go t...
Foreign Key to non-primary key
... key, otherwise, data-garbage is the result sooner rather than later...
Now what you can do in this case (short of rewritting the entire application) is inserting a CHECK-constraint, with a scalar function checking the presence of the key:
IF EXISTS (SELECT * FROM sys.check_constraints WHERE ob...
Why is IoC / DI not common in Python?
...Python, I simply import from a different location using the same name. But now I am thinking if it's also possible the other way round by defining a MyClassInstances class to each MyClass in Java, which contains only static, fully initialized instances. That would be wired :D
–...
What is an IndexOutOfRangeException / ArgumentOutOfRangeException and how do I fix it?
... (nullables has been introduced with .NET 2.0 and anyway it's also a well-known convention in use from many years) if they didn't find anything. Let's imagine you have an array of objects comparable with a string. You may think to write this code:
// Items comparable with a string
Console.WriteLine...
Split delimited strings in a column and insert as new rows [duplicate]
...
Now you can use tidyr 0.5.0's separate_rows is in place of strsplit + unnest.
For example:
library(tidyr)
(df <- read.table(textConnection("1|a,b,c\n2|a,c\n3|b,d\n4|e,f"), header = F, sep = "|", stringsAsFactors = F))
...
How are 3D games so efficient? [closed]
...
Eeeeek!
I know that this question is old, but its exciting that no one has mentioned VSync!!!???
You compared the CPU usage of the game at 60fps to CPU usage of the teapot demo at 60fps.
Isn't it apparent, that both run (more or less)...
Instance variables vs. class variables in Python
...else it's code created by an aberrant programmer wanting to show off they know some obscure corner of Python programming.
Alex mentions in his reply that access will be (a little bit) faster due to one less level of lookup... let me further clarify for those who don't know about how this works yet....