Today I Learned

hashrocket A Hashrocket project

Ruby Data class to replace Struct

Ruby has a new-ish class to build "immutable" structs, check this out:

Measure = Data.define(:amount, :unit)
distance =, 'km')

#=> 100

#=> "km"

And if you try to use a setter, then it will fail:

 distance.amount = 101
(irb):7:in `<main>': undefined method `amount=' for an instance of Measure (NoMethodError)
See More #ruby TILs
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