struct Hash::View(K, V)

• Hash::View(K, V)
• Struct
• Value
• Object

Overview

A HashView is a read-only version of a Hash. This is useful to give access to a non-modifiable hash in a type-safe manner.

The functionality of HashView is limited by design, as it just delegates the non-writable methods to the enclosed hash.

arr = HashView.new({"a" => 1, "b" => 2})
arr.size        # => 2
arr["a"]        # => 1
arr.select "b"  # => {"b" => 2}
arr.select! "b" # does not compile
arr["c"] = 3    # does not compile

Included Modules

• Enumerable({K, V})
• Iterable({K, V})

Defined in:

Constructors

• .new(hash : Hash(K, V) = {} of K => V)

Instance Method Summary

• #==(rhs : Hash(K, V)) : Bool
• #==(rhs : self) : Bool
• #[](*args, **options)
• #[](*args, **options, &)
• #[]?(*args, **options)
• #[]?(*args, **options, &)
• #compact(*args, **options)
• #compact(*args, **options, &)
• #dig(*args, **options)
• #dig(*args, **options, &)
• #dig?(*args, **options)
• #dig?(*args, **options, &)
• #each(*args, **options)
• #each(*args, **options, &)
• #each_key(*args, **options)
• #each_key(*args, **options, &)
• #each_value(*args, **options)
• #each_value(*args, **options, &)
• #empty?(*args, **options)
• #empty?(*args, **options, &)
• #fetch(*args, **options)
• #fetch(*args, **options, &)
• #first_key(*args, **options)
• #first_key(*args, **options, &)
• #first_key?(*args, **options)
• #first_key?(*args, **options, &)
• #first_value(*args, **options)
• #first_value(*args, **options, &)
• #first_value?(*args, **options)
• #first_value?(*args, **options, &)
• #has_key?(*args, **options)
• #has_key?(*args, **options, &)
• #has_value?(*args, **options)
• #has_value?(*args, **options, &)
• #inspect(io : IO) : Nil

  Appends this struct's name and instance variables names and values to the given IO.

• #invert(*args, **options)
• #invert(*args, **options, &)
• #key_for(*args, **options)
• #key_for(*args, **options, &)
• #key_for?(*args, **options)
• #key_for?(*args, **options, &)
• #keys(*args, **options)
• #keys(*args, **options, &)
• #last_key(*args, **options)
• #last_key(*args, **options, &)
• #last_key?(*args, **options)
• #last_key?(*args, **options, &)
• #last_value(*args, **options)
• #last_value(*args, **options, &)
• #last_value?(*args, **options)
• #last_value?(*args, **options, &)
• #merge(*args, **options)
• #merge(*args, **options, &)
• #pretty_print(*args, **options)
• #pretty_print(*args, **options, &)
• #proper_subset_of?(*args, **options)
• #proper_subset_of?(*args, **options, &)
• #proper_superset_of?(*args, **options)
• #proper_superset_of?(*args, **options, &)
• #reject(*args, **options)
• #reject(*args, **options, &)
• #select(*args, **options)
• #select(*args, **options, &)
• #size(*args, **options)
• #size(*args, **options, &)
• #subset_of?(*args, **options)
• #subset_of?(*args, **options, &)
• #superset_of?(*args, **options)
• #superset_of?(*args, **options, &)
• #to_a(*args, **options)
• #to_a(*args, **options, &)
• #to_h(*args, **options)
• #to_h(*args, **options, &)
• #to_s(*args, **options)
• #to_s(*args, **options, &)
• #transform_keys(*args, **options)
• #transform_keys(*args, **options, &)
• #transform_values(*args, **options)
• #transform_values(*args, **options, &)
• #values(*args, **options)
• #values(*args, **options, &)
• #values_at(*args, **options)
• #values_at(*args, **options, &)

Constructor Detail

Instance Method Detail

struct Point
  def initialize(@x : Int32, @y : Int32)
  end
end

p1 = Point.new 1, 2
p1.to_s    # "Point(@x=1, @y=2)"
p1.inspect # "Point(@x=1, @y=2)"