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Rails: convert UTC DateTime to another time zone
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time.in_time_zone(time_zone)
Example:
zone = ActiveSupport::TimeZone.new("Central Time (US & Canada)")
Time.now.in_time_zone(zone)
or just
Time.now.in_time_zone("Central Time (US & Canada)")
You can find the names of the ActiveSupport time zones by doing:
ActiveSupp...
Multi-line commands in GHCi
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Most of the time, you can rely on type inference to work out a signature for you. In your example, the following is sufficient:
Prelude> let addTwo x y = x + y
If you really want a definition with a type signature, or your definition spans over multiple lines, you can do ...
What is string_view?
...arlier ones called string_ref and array_ref, too.
The idea is always to store a pair of pointer-to-first-element and size of some existing data array or string.
Such a view-handle class could be passed around cheaply by value and would offer cheap substringing operations (which can be implemented ...
bash: Bad Substitution
This bash script gives me Bad substitution error on Ubuntu. Any help will be highly appreciated.
11 Answers
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How to do associative array/hashing in JavaScript
I need to store some statistics using JavaScript in a way like I'd do it in C#:
11 Answers
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Removing multiple keys from a dictionary safely
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the_dict = {'b': 'foo'}
def entries_to_remove(entries, the_dict):
for key in entries:
if key in the_dict:
del the_dict[key]
A more compact version was provided by mattbornski using dict.pop()
sh...
Why are only final variables accessible in anonymous class?
...Only an effectively final variable can be used in an anonymous inner class or lambda expression though.
It's basically due to the way Java manages closures.
When you create an instance of an anonymous inner class, any variables which are used within that class have their values copied in via the...
How do I automatically sort a has_many relationship in Rails?
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You can specify the sort order for the bare collection with an option on has_many itself:
class Article < ActiveRecord::Base
has_many :comments, :order => 'created_at DESC'
end
class Comment < ActiveRecord::Base
belongs_to :artic...
Should I initialize variable within constructor or outside constructor [duplicate]
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I find the second style (declaration + initialization in one go) superior. Reasons:
It makes it clear at a glance how the variable is initialized. Typically, when reading a program and coming across a variable, you'll first go to its declaration (often automatic in IDEs). With style 2, you see...
Can't use NVM from root (or sudo)
...hatever version of node you have active via nvm into the /usr/local/ directory (where user installed global files should live on a linux VPS) and setting the permissions so that all users can access them.
Hope this helps!
s...