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Count, size, length…too many choices in Ruby?
...ke an element or predicate and count only those items that match.
> [1,2,3].count{|x| x > 2 }
=> 1
In the case where you don't provide a parameter to count it has basically the same effect as calling length. There can be a performance difference though.
We can see from the source code...
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, :uniquenes...
Using “label for” on radio buttons
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218
You almost got it. It should be this:
<input type="radio" name="group1" id="r1" value=...
Rails - controller action name to string
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Rails 2.X: @controller.action_name
Rails 3.1.X: controller.action_name, action_name
Rails 4.X: action_name
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jQuery find parent form
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answered Oct 25 '09 at 18:58
karim79karim79
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Create a variable name with “paste” in R?
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125
You can use assign (doc) to change the value of perf.a1:
> assign(paste("perf.a", "1", sep=...
Measure time in Linux - time vs clock vs getrusage vs clock_gettime vs gettimeofday vs timespec_get?
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2 Answers
2
Active
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Make page to tell browser not to cache/preserve input values
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answered Apr 23 '10 at 14:38
DisgruntledGoatDisgruntledGoat
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Python string.join(list) on object array rather than string array
...r x in list)
– dF.
Jan 31 '09 at 0:12
1
any idea on which of them would be faster?
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How do I delete a fixed number of rows with sorting in PostgreSQL?
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answered Mar 2 '11 at 18:01
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