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When does static class initialization happen?
...nstantiate a class, but I access a static field, are ALL the static blocks and private static methods used to instantiate private static fields called (in order) at that instant?
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Best way of invoking getter by reflection
...will always have a getter method. I know that I can use setAccesible(true) and get its value (when there is no PermissionManager), though I prefer to invoke its getter method.
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C++ equivalent of java's instanceof
...e of course).
As pointed out dynamic_cast doesn't come for free. A simple and consistently performing hack that handles most (but not all cases) is basically adding an enum representing all the possible types your class can have and check whether you got the right one.
if(old->getType() == BOX...
Ruby custom error classes: inheritance of the message attribute
... you don't have to pass it to the constructor:
class MyCustomError < StandardError
attr_reader :object
def initialize(object)
@object = object
end
end
begin
raise MyCustomError.new("an object"), "a message"
rescue MyCustomError => e
puts e.message # => "a message"
puts e....
How to round up to the nearest 10 (or 100 or X)?
...en James answer seems most appropriate. My version lets you take any value and automatically round it to a reasonably "nice" value. Some other good choices of the "nice" vector above are: 1:10, c(1,5,10), seq(1, 10, 0.1)
If you have a range of values in your plot, for example [3996.225, 40001.893] ...
github locks up mac terminal when using pull command
I'm in the process of learning github on mac (command-line) and whenever I do git pull origin master i get this
8 Answers...
Fully custom validation error message with Rails
...
Now, the accepted way to set the humanized names and custom error messages is to use locales.
# config/locales/en.yml
en:
activerecord:
attributes:
user:
email: "E-mail address"
errors:
models:
user:
attributes:
e...
Unrecognized SSL message, plaintext connection? Exception
...
I have the same error, and I solved when I started using http instead of https. But when I place the link in browser with https it works! And I need to perform a safe query. Any idea on how can I solve the problem?
– ccoutinho...
Removing index column in pandas when reading a csv
I have the following code which imports a CSV file. There are 3 columns and I want to set the first two of them to variables. When I set the second column to the variable "efficiency" the index column is also tacked on. How can I get rid of the index column?
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JavaScript function order: why does it matter?
...further down the page than the call to it. However, my page is for a game, and no functions are called until the whole thing has downloaded. So why does the order functions appear in my code matter?
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