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Rails hidden field undefined method 'merge' error
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You should do:
<%= f.hidden_field :service, :value => "test" %>
hidden_field expects a hash as a second argument
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How can I set the request header for curl?
...;q=0.8,en;q=0.6' \
-e localhost \
-A 'Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/29.0.1547.65 Safari/537.36' \
'http://restapi.some-site.com/getsomething?argument=value&argument2=value'
In this example the referer (-e or --referer in curl) is '...
TCP vs UDP on video stream
...say you are streaming a soccer match, or concert for that matter, do you really need to use UDP?
13 Answers
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rails 3 validation on uniqueness on multiple attributes
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In Rails 2, I would have written:
validates_uniqueness_of :zipcode, :scope => :recorded_at
In Rails 3:
validates :zipcode, :uniqueness => {:scope => :recorded_at}
For multiple attributes:
validates :zipcode, :uniqueness => {:scope => [:recorded_at...
What are the differences between Abstract Factory and Factory design patterns?
...le the desired object
instantiation.
The quote assumes that an object is calling its own factory method here. Therefore the only thing that could change the return value would be a subclass.
The abstract factory is an object that has multiple factory methods on it. Looking at the first half of your...
How to select the nth row in a SQL database table?
...upports the standard windowing functions:
SELECT * FROM (
SELECT
ROW_NUMBER() OVER (ORDER BY key ASC) AS rownumber,
columns
FROM tablename
) AS foo
WHERE rownumber <= n
(which I just copied from the site linked above since I never use those DBs)
Update: As of PostgreSQL 8.4 the st...
What is the difference between SIGSTOP and SIGTSTP?
...
/usr/include/x86_64-linux-gnu/bits/signum.h
#define SIGSTOP 19 /* Stop, unblockable (POSIX). */
#define SIGTSTP 20 /* Keyboard stop (POSIX). */
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Can I return the 'id' field after a LINQ insert?
...? there is no insertonsubmit or submitchanges??
– Bat_Programmer
Jul 4 '12 at 0:35
1
@Confused Pr...
How can I change image tintColor in iOS and WatchKit
...; ())
/// - Returns: UIImage
fileprivate func modifiedImage(_ draw: (CGContext, CGRect) -> ()) -> UIImage {
// using scale correctly preserves retina images
UIGraphicsBeginImageContextWithOptions(size, false, scale)
let context: CGContext! = UIGr...
How to disable JavaScript in Chrome Developer Tools?
...sable-javascript doesn't work with google-chrome-stable-51.0.2704.106-1.x86_64.
– Cristian Ciupitu
Jul 16 '16 at 20:44
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