Declutters your Ruby hashes and arrays by removing empty arrays and hashes.
Also has options for removing nils, redundancies and falses, and objects that
respond to #declutter.
In this simple example, we create a hash structure that contains an empty array:
#!/usr/bin/ruby -w
require 'declutter'
myhash = { 'title' => 'Titus Andronicus', 'episodes' => [] }
puts myhash # => {"title"=>"Titus Andronicus", "episodes"=>[]}
Declutter.process myhash
puts myhash # => {"title"=>"Titus Andronicus"}By running the hash through Declutter.process, we remove the empty array. If
an array contains only an empty array, then the whole array structure is
removed:
myhash = { 'title' => 'Titus Andronicus', 'episodes' => ['scenes'=>[]] };
puts myhash # => {"title"=>"Titus Andronicus", "episodes"=>[{"scenes"=>[]}]}
Declutter.process myhash
puts myhash # => {"title"=>"Titus Andronicus"}The same concept goes for empty hashes:
myhash = {'title' => 'Titus Andronicus', 'notes' => {'ideas'=>{}} }
puts myhash # => {"title"=>"Titus Andronicus", "notes"=>{}}
Declutter.process myhash
puts myhash # => {"title"=>"Titus Andronicus"}To refine what elements are deleted, instantiate Declutter to set what type of
elements are deleted.
To delete nils, set declutter.delete_nils to true:
myhash = { 'episodes'=>['pilot', nil, 'transition'] }
puts myhash # => {"episodes"=>["pilot", nil, "transition"]}
declutter = Declutter.new()
declutter.delete_nils = true
declutter.process myhash
puts myhash # => {"episodes"=>["pilot", "transition"]}If deleting the nil values results in an empty array, then the array is deleted.
myhash = { 'episodes'=>[nil] }
puts myhash # => { 'episodes'=>[nil] }
declutter = Declutter.new()
declutter.delete_nils = true
declutter.process myhash
puts myhash # => {}To delete redundant elements in arrays, set declutter.delete_redundancies to
true.
myhash = { 'episodes'=>['pilot', 'pilot'] }
puts myhash # => { 'episodes'=>['pilot', 'pilot'] }
declutter = Declutter.new()
declutter.delete_redundancies = true
declutter.process myhash
puts myhash # => { 'episodes'=>['pilot'] }To delete false values, set declutter.delete_falses to true:
myhash = { 'episodes'=>['pilot', false] }
puts myhash # => {"episodes"=>["pilot", false]}
declutter = Declutter.new()
declutter.delete_falses = true
declutter.process myhash
puts myhash # => {"episodes"=>["pilot"]}To keep empty hashes, set declutter.delete_empty_hashes to false:
myhash = { 'episodes'=>[], 'notes'=>{} }
puts myhash # => {"episodes"=>[], "notes"=>{}}
declutter = Declutter.new()
declutter.delete_empty_hashes = false
declutter.process myhash
puts myhash # => {"notes"=>{}}To keep empty arrays, set declutter.delete_empty_arrays to false:
myhash = { 'episodes'=>[], 'notes'=>{} }
puts myhash # => {"episodes"=>[], "notes"=>{}}
declutter = Declutter.new()
declutter.delete_empty_arrays = false
declutter.process myhash
puts myhash # => {"episodes"=>[]}Objects of your own custom class can be decluttered if they have a #declutter
method. Consider these two classes.
class KeepMe
def declutter
return true
end
end
class DeleteMe
def declutter
return false
end
endBoth classes have declutter methods. KeepMe#declutter returns true and
DeleteMe#declutter returns false. In this first example, we use the default
settings to declutter the hash.
hsh = {}
hsh['keep-it'] = KeepMe.new
hsh['delete-it'] = DeleteMe.new
Declutter.process hsh
puts hsh # => {"keep-it"=>#<KeepMe:0x0000559f8574b718>}The keep-it element was kept because KeepMe#declutter returns true. However,
the delete-it element was deleted because DeleteMe#declutter returns false.
To bypass decluttering objects that have a #declutter method, use the object
oriented approach and set process_others to false:
hsh = {}
hsh['keep-it'] = KeepMe.new
hsh['delete-it'] = DeleteMe.new
declutter = Declutter.new
declutter.process_others = false
declutter.process hsh
puts hsh # => {"keep-it"=>#<KeepMe:0x000055e5ffd46f80>, "delete-it"=>#<DeleteMe:0x000055e5ffd46f30>}| date | version | notes |
|---|---|---|
| May 23, 2023 | 1.0 | Initial upload. |
