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What underlies this JavaScript idiom: var self = this?
...in event handlers (especially in closures).
Edit: Note that using self is now discouraged as window.self exists and has the potential to cause errors if you are not careful.
What you call the variable doesn't particularly matter. var that = this; is fine, but there's nothing magic about the name....
What does “abstract over” mean?
... (implicit ff: Foldable[F], m: Monoid[B]) =
ff.foldMap(as, f)
Now we have something quite general. The method mapReduce will fold any F[A] given that we can prove that F is foldable and that A is a monoid or can be mapped into one. For example:
case class Sum(value: Int)
case class Pro...
PostgreSQL Autoincrement
... @Dr Deo : they use serial instead autoincrement keyword, i don't know why :)
– Ahmad
Jul 22 '12 at 7:16
4
...
What version of Visual Studio is Python on my computer compiled with?
...obscure, lesson 1! Thanks this though Drorhan, it's definitely a "nice to know"!
– dm76
Apr 20 '10 at 16:37
A little l...
Installed Ruby 1.9.3 with RVM but command line doesn't show ruby -v
...thing to RVM that produces lots of errors, the only safe way of fixing for now is to:
sudo apt-get --purge remove ruby-rvm
sudo rm -rf /usr/share/ruby-rvm /etc/rvmrc /etc/profile.d/rvm.sh
open new terminal and validate environment is clean from old RVM settings (should be no output):
env | grep ...
ActiveModel::ForbiddenAttributesError when creating new user
...pecify in
each controller)
Additionally, load_and_authorize_resource can now take a param_method option to specify a custom method in the controller to run to sanitize input.
You can associate the param_method option with a symbol corresponding to the name of a method that will get called:
class...
Primary key or Unique index?
...e a composed primary key (person_id, car_id)?
– unbeknown
Jan 28 '09 at 12:20
3
primary key (pers...
Regex for password must contain at least eight characters, at least one number and both lower and up
...avor, \W matches only ASCII characters. So you haven't changed that, and now you have to filter out whitespace characters. Furthermore, all the parentheses and {1,} quantifiers you added are pure noise, and removing the non-greedy (?) operators was pointless. There is no improvement here.
...
Run an OLS regression with Pandas Data Frame
...red positional argument: 'endog', so i guess it's deprecated. also, ols is now OLS
– 3pitt
May 18 '18 at 18:50
...
Simple Digit Recognition OCR in OpenCV-Python
... letter_recognition.data file that comes with OpenCV samples. I wanted to know what is inside that file.
It contains a letter, along with 16 features of that letter.
And this SOF helped me to find it. These 16 features are explained in the paperLetter Recognition Using Holland-Style Adaptive Class...