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instance method

Data#to_h

() -> ::Hash[::Symbol, untyped]

to_h → hash

to_h {|name, value| ... } → hash

#define rb_data_to_h rb_struct_to_h

Returns Hash representation of the data object.

Example

Measure = Data.define(:amount, :unit)
distance = Measure[10, 'km']

distance.to_h
#=> {amount: 10, unit: "km"}

Like Enumerable#to_h, if the block is provided, it is expected to produce key-value pairs to construct a hash:

Example

distance.to_h { |name, val| [name.to_s, val.to_s] }
#=> {"amount"=>"10", "unit"=>"km"}

Note that there is a useful symmetry between to_h and initialize:

Example

distance2 = Measure.new(**distance.to_h)
#=> #<data Measure amount=10, unit="km">
distance2 == distance
#=> true

See also #members #to_s #inspect #with also in 4.0 · 3.4 · 3.3 · 3.2