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@KonnorRogers
Last active June 17, 2021 14:53
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Using hashes for structs
# using a predefined hash
hash = { field1: "foo", field2: "bar" }
HashStruct = Struct.new(*hash.keys, keyword_init: true)
hash_struct = HashStruct.new(hash)
hash_struct.field1 # => "foo"
hash_struct.field2 # => "bar"
hash_struct.field3 # => ERROR!
# using an array
ary = [:field1, :field2]
AryStruct = Struct.new(*ary, keyword_init: true)
ary_hash = {}
ary_hash[:field1] = "foo"
ary_hash[:field2] = "bar"
ary_struct = AryStruct.new(ary_hash)
ary_struct.field1 # => "foo"
ary_struct.field2 # => "bar"
ary_struct.field3 # => ERROR!
@KonnorRogers
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@sajanbasnet75 I havent really thought aboutt this use case too much. I really only thought about top-level objects.

For a nested hash to use dot notation, if youre using Rails, you could do something like this:

h = ActiveSupport::InheritableOptions.new({ 'company' => [{ 'name' => 'Company1', 'departments': [{ 'name' => 'Management' }] },
                                                                                                    { 'name' => 'Company2', 'departments': [{ 'name' => 'Engineering' }] }] )})

which then allows you to do:

h.company.first.departments.first

@sajanbasnet75
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sajanbasnet75 commented Jun 17, 2021

Thanks for the reply @ParamagicDev

Unfortunately, I am trying to do this on plain ruby, also using Struct rather than openStruct.

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