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39 lines
975 B
Markdown
39 lines
975 B
Markdown
# Create Named Structs With Struct.new
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I often see `Struct` used to create some one-off anonymous data structure
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like so:
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```ruby
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> person = Struct.new(:name, :age)
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=> #<Class:0x007fc6c89112e8>
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> person.new("Alice", 33)
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=> #<struct name="Alice", age=33>
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```
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This will often get the job done, but on its own the resulting data
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structure doesn't tell us as much as it could.
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We can say more with a _named_ struct:
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```ruby
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Struct.new("Person", :name, :age)
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=> Struct::Person
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> Struct::Person.new("Bob", 24)
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=> #<struct Struct::Person name="Bob", age=24>
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```
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When the first argument is a string that can be converted to a constant,
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then we'll get a named struct that is subclassed under `Struct`.
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We can also assign the struct initialization to a constant to do a similar
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thing:
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```ruby
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> Person = Struct.new(:name, :age)
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=> Person
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> Person.new("Jerry", 45)
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=> #<struct Person name="Jerry", age=45>
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```
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[source](https://ruby-doc.org/core-2.4.2/Struct.html#method-c-new)
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