struct JSON::Any

• JSON::Any
• Struct
• Value
• Object

Overview

JSON::Any is a convenient wrapper around all possible JSON types (JSON::Any::Type) and can be used for traversing dynamic or unknown JSON structures.

require "json"

obj = JSON.parse(%({"access": [{"name": "mapping", "speed": "fast"}, {"name": "any", "speed": "slow"}]}))
obj["access"][1]["name"].as_s  # => "any"
obj["access"][1]["speed"].as_s # => "slow"

Note that methods used to traverse a JSON structure, #[] and #[]?, always return a JSON::Any to allow further traversal. To convert them to String, Int32, etc., use the as_ methods, such as #as_s, #as_i, which perform a type check against the raw underlying value. This means that invoking #as_s when the underlying value is not a String will raise: the value won't automatically be converted (parsed) to a String. There are also nil-able variants (#as_i?, #as_s?, ...), which return nil when the underlying value type won't match.

Defined in:

Constructors

• .new(raw : Type)

  Creates a JSON::Any that wraps the given value.

• .new(pull : JSON::PullParser)

  Reads a JSON::Any value from the given pull parser.

Instance Method Summary

• #==(other : JSON::Any)

  Returns true if both self and other's raw object are equal.

• #==(other)

  Returns true if the raw object is equal to other.

• #[](index : Int) : JSON::Any

  Assumes the underlying value is an Array and returns the element at the given index.

• #[](key : String) : JSON::Any

  Assumes the underlying value is a Hash and returns the element with the given key.

• #[]?(index : Int) : JSON::Any?

  Assumes the underlying value is an Array and returns the element at the given index, or nil if out of bounds.

• #[]?(key : String) : JSON::Any?

  Assumes the underlying value is a Hash and returns the element with the given key, or nil if the key is not present.

• #as_a : Array(Any)

  Checks that the underlying value is Array, and returns its value.

• #as_a? : Array(Any)?

  Checks that the underlying value is Array, and returns its value.

• #as_bool : Bool

  Checks that the underlying value is Bool, and returns its value.

• #as_bool? : Bool?

  Checks that the underlying value is Bool, and returns its value.

• #as_f : Float64

  Checks that the underlying value is Float, and returns its value as an Float64.

• #as_f32 : Float32

  Checks that the underlying value is Float, and returns its value as an Float32.

• #as_f32? : Float32?

  Checks that the underlying value is Float, and returns its value as an Float32.

• #as_f? : Float64?

  Checks that the underlying value is Float, and returns its value as an Float64.

• #as_h : Hash(String, Any)

  Checks that the underlying value is Hash, and returns its value.

• #as_h? : Hash(String, Any)?

  Checks that the underlying value is Hash, and returns its value.

• #as_i : Int32

  Checks that the underlying value is Int, and returns its value as an Int32.

• #as_i64 : Int64

  Checks that the underlying value is Int, and returns its value as an Int64.

• #as_i64? : Int64?

  Checks that the underlying value is Int, and returns its value as an Int64.

• #as_i? : Int32?

  Checks that the underlying value is Int, and returns its value as an Int32.

• #as_nil : Nil

  Checks that the underlying value is Nil, and returns nil.

• #as_s : String

  Checks that the underlying value is String, and returns its value.

• #as_s? : String?

  Checks that the underlying value is String, and returns its value.

• #clone

  Returns a new JSON::Any instance with the #raw value #cloneed.

• #dig(index_or_key : String | Int, *subkeys) : JSON::Any

  Traverses the depth of a structure and returns the value, otherwise raises.

• #dig?(index_or_key : String | Int, *subkeys) : JSON::Any?

  Traverses the depth of a structure and returns the value.

• #dup

  Returns a new JSON::Any instance with the #raw value #duped.

• #hash(hasher)

  See Object#hash(hasher)

• #inspect(io : IO) : Nil

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

• #raw : Type

  Returns the raw underlying value.

• #size : Int

  Assumes the underlying value is an Array or Hash and returns its size.

• #to_s(io : IO) : Nil

  Same as #inspect(io).

• #to_yaml(yaml : YAML::Nodes::Builder) : Nil

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)"