struct

JSON::Any

Inherits Struct / Value / Object

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.

Constructors

new(raw : Type)

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

new(raw : Int) : self

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

new(raw : Float) : self

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

new(pull : JSON::PullParser) : self

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

Instance methods

==(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. Raises if the underlying value is not an Array.

[](key : String) : JSON::Any

Assumes the underlying value is a Hash and returns the element with the given key. Raises if the underlying value is not a Hash.

[]?(index : Int) : JSON::Any | Nil

Assumes the underlying value is an Array and returns the element at the given index, or nil if out of bounds. Raises if the underlying value is not an Array.

[]?(key : String) : JSON::Any | Nil

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

as_a

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

as_a?

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

as_bool

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

as_bool?

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

as_f

Checks that the underlying value is Float (or Int), and returns its value as an Float64. Raises otherwise.

as_f32

Checks that the underlying value is Float (or Int), and returns its value as an Float32. Raises otherwise.

as_f32?

Checks that the underlying value is Float (or Int), and returns its value as an Float32. Returns nil otherwise.

as_f?

Checks that the underlying value is Float (or Int), and returns its value as an Float64. Returns nil otherwise.

as_h

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

as_h?

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

as_i

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

as_i64

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

as_i64?

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

as_i?

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

as_nil

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

as_s

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

as_s?

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

clone

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

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

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

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

Traverses the depth of a structure and returns the value. Returns nil if not found.

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.

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)"

raw

Returns the raw underlying value.

size

Assumes the underlying value is an Array or Hash and returns its size. Raises if the underlying value is not an Array or Hash.

to_s(io : IO) : Nil

Same as #inspect(io).

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

Nested types

JSON::Any::Type