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Interface or an Abstract Class: which one to use?
...cluded) to implement a set numbers of methods and you want to provide some base methods that will help them develop their child classes.
Another thing to keep in mind is client classes can only extend one abstract class, whereas they can implement multiple interfaces. So, if you're defining your...
Difference between CR LF, LF and CR line break types?
...nning of the line. This character is used as a new line character in UNIX based systems (Linux, Mac OSX, etc)
The End of Line (EOL) sequence (0x0D 0x0A, \r\n) is actually two ASCII characters, a combination of the CR and LF characters. It moves the cursor both down to the next line and to the beg...
Ignoring a class property in Entity Framework 4.1 Code First
...
{
modelBuilder.Entity<Customer>().Ignore(t => t.LastName);
base.OnModelCreating(modelBuilder);
}
http://msdn.microsoft.com/en-us/library/hh295847(v=vs.103).aspx
The version I checked is EF 4.3, which is the latest stable version available when you use NuGet.
Edit : SEP 2017
Asp.NE...
What are good uses for Python3's “Function Annotations”
...uses for annotations beyond assurance. I can see how I could apply my Java-based tools to Python. For instance, I have a tool that lets you assign special warnings to methods, and gives you indications when you call them that you should read their documentation (E.g., imagine you have a method that ...
Could not load NIB in bundle
... (use a storyboard):
For some reason it changed from "Main storyboard file base name" to "Main nib file base name" in the plist.
Changing back to "Main storyboard file base name" (UIMainStoryboardFile) solved the issue
shar...
Why can't I inherit static classes?
...
Other opinions from channel9
Inheritance in .NET works only on instance base. Static methods are defined on the type level not on the instance level. That is why overriding doesn't work with static methods/properties/events...
Static methods are only held once in memory. There is no virtual table...
How to print out the contents of a vector?
...re complicated objects where this solution is not going to be ideal.
range-based for loop (C++11)
See Jefffrey's solution. In C++11 (and later) you can use the new range-based for loop, which looks like this:
for (auto i: path)
std::cout << i << ' ';
Since path is a vector of items (e...
Tool to Unminify / Decompress JavaScript [closed]
...ne only formats the code, it doesn't change variable names, nor uncompress base62 encoding.
edit: in fact it can unpack "packed" scripts (packed with Dean Edward's packer : http://dean.edwards.name/packer/)
share
|...
Run a callback only if an attribute has changed in Rails
...
Rails 5.1+
class Page < ActiveRecord::Base
before_save :do_something, if: :will_save_change_to_status_id?
private
def do_something
# ...
end
end
The commit that changed ActiveRecord::Dirty is here: https://github.com/rails/rails/commit/16ae3db5a5c...
Extracting the last n characters from a string in R
...
I'm not aware of anything in base R, but it's straight-forward to make a function to do this using substr and nchar:
x <- "some text in a string"
substrRight <- function(x, n){
substr(x, nchar(x)-n+1, nchar(x))
}
substrRight(x, 6)
[1] "string"...