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45 lines
1.1 KiB
Markdown
45 lines
1.1 KiB
Markdown
# Skip The Front Of An Array With Drop
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I've long been familiar with Ruby's
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[`Array#take`](https://apidock.com/ruby/Array/take) which is a handy way to
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grab the first few elements of an array.
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```ruby
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> [:a, :b, :c, :d, :e, :f, :g].take(4)
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=> [:a, :b, :c, :d]
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```
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But what if I want to skip those first four elements of the array and get what
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remains. That is where [`Array#drop`](https://apidock.com/ruby/Array/drop)
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comes in.
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```ruby
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> [:a, :b, :c, :d, :e, :f, :g].drop(4)
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=> [:e, :f, :g]
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```
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How about a couple practical situations for use in a Rails app.
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Here I want to segment out the first 6 books and whatever remains:
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```
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def index
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@books = Book.order(created_at: :desc).limit(10)
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@featured_books = @books.take(6)
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@remaining_books = @books.drop(6)
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end
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```
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Or, what about cleaning up all but the first of these duplicate records:
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```
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Book
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.where(title: "The Murder of Roger Ackroyd")
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.drop(1)
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.each { |duplicate_book| duplicate_book.destroy }
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```
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The first record is ignored (dropped from the array) and the following records
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are processed by the `#each` where they get destroyed.
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