struct Null

Defined in:

nason/null.cr

Constructors

Instance Method Summary

Instance methods inherited from struct Value

==(other : NASON::Any) ==

Instance methods inherited from class Object

===(other : NASON::Any) ===, nil_or_null? nil_or_null?, not_null! not_null!, null? null?, to_nason(io : IO) : Nil
to_nason : String to_nason, to_pretty_json(indent : String = " ") : String
to_pretty_json(io : IO, indent : String = " ") : Nil to_pretty_json

Class methods inherited from class Object

from_nason(string_or_io, root : String)
from_nason(string_or_io) from_nason

Constructor Detail

def self.new(pull : NASON::PullParser) #

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def self.new #

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def self.null : Null #

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Instance Method Detail

def ==(other : Null) #

Returns 0_u64. Even though Null is not a Reference type, it is usually mixed with them to form nilable types so it's useful to have an object id for nil. Returns true: Null has only one singleton value: nil.


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def clone #

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def inspect(io : IO) : Nil #

Writes "null" to the given IO.


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def inspect : String #

Returns "nil".


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def not_nil! : Null #

Raises NullAssertionError.

See also: Object#not_nil!.


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def not_null! : NoReturn #

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def presence : Nil #

Returns self. This method enables to call the #presence method (see String#presence) on a union with Null. The idea is to return nil when the value is nil or empty.

config = {"empty" => ""}
config["empty"]?.presence   # => nil
config["missing"]?.presence # => nil

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def same?(other : Null) #

Returns true: Null has only one singleton value: nil.


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def same?(other : Reference) : Bool #

Returns false.


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def to_json_object_key : String #

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def to_nason(nson : NASON::Builder) : Nil #

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def to_s(io : IO) : Nil #

Appends "null" to the given IO.


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def to_s : String #

Returns "null"


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

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def try(&) #

Doesn't yield to the block.

See also: Object#try.


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