У меня есть:
fruits = {
"orange" => {:season => "winter"},
"apple" => {:season => "winter"},
"banana" => {:season => "summer"},
"grape" => {:season => "spring"},
"peach" => {:season => "winter"},
"pineapple" => {:season => "summer"}
}
Я хочу получить:
{
"winter"=>["orange", "apple", "peach"],
"summer"=>["banana", "pineapple"],
"spring"=>["grape"]
}
Я сделал:
def sort_fruits(fruits_hash)
fruits=[]
sorted = {}
seasons = fruits_hash.map {|k, v|v[:season]}
seasons.uniq.each do |season|
fruits.clear
fruits_hash.each do |fruit, season_name|
if season == season_name[:season]
fruits << fruit
end
end
p sorted[season] = fruits ## season changes to new season, so this should have created new key/value pair for new season.
end
sorted
end
Я получил:
{
"winter"=>["grape"],
"summer"=>["grape"],
"spring"=>["grape"]
}
Я не мог понять, почему добавление новой пары ключ/значение с уникальным ключом перезаписывает существующую пару в хеше. Любая помощь с объяснением будет принята с благодарностью.
fruits.group_by { |k,v| v[:season] }.transform_values {|v| v.map(&:first) }
- person Marcin Kołodziej   schedule 14.10.2018