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49 lines
783 B
Markdown
49 lines
783 B
Markdown
# Turning Things Into Hashes
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We have `#to_h` for turning things into hashes.
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It works as an identity function:
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```ruby
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> {}.to_h
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=> {}
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> {hello: "world"}.to_h
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=> {:hello=>"world"}
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```
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It works with `nil`:
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```ruby
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> nil.to_h
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=> {}
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```
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Does it work with arrays?
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```ruby
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> [:one, 2].to_h
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TypeError: wrong element type Symbol at 0 (expected array)
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from (pry):36:in `to_h'
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```
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Yes, but only if it is an array of pairs:
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```ruby
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> [[:one, 2], [:three, 4]].to_h
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=> {:one=>2, :three=>4}
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```
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It also works with `Struct` and `OpenStruct`:
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```
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> Person = Struct.new(:name, :age)
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=> Person
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> bob = Person.new("bob", 45)
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=> #<struct Person name="bob", age=45>
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> bob.to_h
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=> {:name=>"bob", :age=>45}
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```
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You'll find that many other objects and gems support `#to_h` when it makes
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sense.
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