class Reference
Overview
Reference
is the base class of classes you define in your program.
It is set as a class' superclass when you don't specify one:
class MyClass # < Reference
end
A reference type is passed by reference: when you pass it to methods, return it from methods or assign it to variables, a pointer is actually passed.
Invoking .new
on a Reference
allocates a new instance on the heap.
The instance's memory is automatically freed (garbage-collected) when
the instance is no longer referred by any other entity in the program.
Direct Known Subclasses
- Array(T)
- Benchmark::BM::Job
- Benchmark::BM::Tms
- Benchmark::IPS::Entry
- Benchmark::IPS::Job
- Box(T)
- Channel(T)
- Crypto::Bcrypt
- Crypto::Bcrypt::Password
- Crypto::Blowfish
- Crystal::Macros::ASTNode
- CSV
- CSV::Builder
- CSV::Lexer
- CSV::Parser
- Deque(T)
- Digest::Base
- Dir
- Exception
- Fiber
- Gzip::Header
- Hash(K, V)
- HTTP::Client
- HTTP::Client::Response
- HTTP::CompressHandler
- HTTP::Cookie
- HTTP::Cookies
- HTTP::ErrorHandler
- HTTP::FormData::Builder
- HTTP::FormData::Parser
- HTTP::LogHandler
- HTTP::Params::Builder
- HTTP::Request
- HTTP::Server
- HTTP::Server::Context
- HTTP::Server::RequestProcessor
- HTTP::StaticFileHandler
- HTTP::WebSocket
- HTTP::WebSocketHandler
- INI
- IO
- Iterator::Stop
- JSON::Builder
- JSON::Lexer
- JSON::Parser
- JSON::PullParser
- JSON::Token
- Levenshtein::Finder
- LLVM::ABI
- LLVM::ABI::FunctionType
- LLVM::Builder
- LLVM::Context
- LLVM::FunctionPassManager
- LLVM::GenericValue
- LLVM::JITCompiler
- LLVM::MemoryBuffer
- LLVM::Module
- LLVM::ModulePassManager
- LLVM::PassManagerBuilder
- LLVM::TargetMachine
- Logger
- MIME::Multipart::Builder
- MIME::Multipart::Parser
- Mutex
- OAuth2::AccessToken
- OAuth2::Client
- OAuth2::Session
- OAuth::AccessToken
- OAuth::Consumer
- OAuth::RequestToken
- OpenSSL::Cipher
- OpenSSL::Digest
- OpenSSL::HMAC
- OpenSSL::MD5
- OpenSSL::SHA1
- OpenSSL::SSL::Context
- OpenSSL::SSL::Server
- OptionParser
- PrettyPrint
- Process
- Process::Status
- Random::ISAAC
- Random::PCG32
- Regex
- Spec::Context
- Spec::Example
- Spec::VerboseFormatter::Item
- String
- StringPool
- StringScanner
- System::Group
- System::User
- Time::Location
- URI
- URI::Punycode
- WeakRef(T)
- YAML::Builder
- YAML::Nodes::Builder
- YAML::Nodes::Node
- YAML::ParseContext
- YAML::PullParser
- Zip::File
- Zip::File::Entry
- Zip::Reader
- Zip::Reader::Entry
- Zip::Writer
- Zip::Writer::Entry
Defined in:
primitives.crreference.cr
json/any.cr
yaml/any.cr
Constructors
Instance Method Summary
-
#==(other : self)
Returns
true
if this reference is the same as other. - #==(other : JSON::Any)
- #==(other : YAML::Any)
-
#==(other)
Returns
false
(other can only be aValue
here). -
#dup
Returns a shallow copy of this object.
- #hash(hasher)
-
#inspect(io : IO) : Nil
Appends a String representation of this object which includes its class name, its object address and the values of all instance variables.
-
#object_id : UInt64
Returns a
UInt64
that uniquely identifies this object. - #pretty_print(pp) : Nil
-
#same?(other : Reference)
Returns
true
if this reference is the same as other. -
#same?(other : Nil)
Returns
false
: a reference is nevernil
. -
#to_s(io : IO) : Nil
Appends a short String representation of this object which includes its class name and its object address.
Instance methods inherited from class Object
! : Bool
!,
!=(other)
!=,
!~(other)
!~,
==(other)
==,
===(other : JSON::Any)===(other : YAML::Any)
===(other) ===, =~(other) =~, as(type : Class) as, as?(type : Class) as?, class class, dup dup, hash
hash(hasher) hash, inspect(io : IO) : Nil
inspect : String inspect, is_a?(type : Class) : Bool is_a?, itself itself, nil? : Bool nil?, not_nil! not_nil!, pretty_inspect(width = 79, newline = "\n", indent = 0) : String pretty_inspect, pretty_print(pp : PrettyPrint) : Nil pretty_print, responds_to?(name : Symbol) : Bool responds_to?, tap(&) tap, to_json(io : IO)
to_json to_json, to_pretty_json(indent : String = " ")
to_pretty_json(io : IO, indent : String = " ") to_pretty_json, to_s : String
to_s(io : IO) : Nil to_s, to_yaml(io : IO)
to_yaml to_yaml, try(&) try, unsafe_as(type : T.class) forall T unsafe_as
Class methods inherited from class Object
from_json(string_or_io, root : String)from_json(string_or_io) from_json, from_yaml(string_or_io : String | IO) from_yaml
Constructor Detail
Instance Method Detail
Returns a shallow copy of this object.
This allocates a new object and copies the contents of
self
into it.
Appends a String representation of this object which includes its class name, its object address and the values of all instance variables.
class Person
def initialize(@name : String, @age : Int32)
end
end
Person.new("John", 32).inspect # => #<Person:0x10fd31f20 @name="John", @age=32>
Returns a UInt64
that uniquely identifies this object.
The returned value is the memory address of this object.
string = "hello"
string.object_id # => 4460249568
pointer = Pointer(String).new(string.object_id)
string2 = pointer.as(String)
string2.object_id == string.object_id # => true
Returns true
if this reference is the same as other. This is only
true
if this reference's #object_id
is the same as other's.
Appends a short String representation of this object which includes its class name and its object address.
class Person
def initialize(@name : String, @age : Int32)
end
end
Person.new("John", 32).to_s # => #<Person:0x10a199f20>