Class: Object - Noobkit

Object is the parent class of all classes in Ruby. Its methods are therefore available to all objects unless explicitly overridden.

Object mixes in the Kernel module, making the built-in kernel functions globally accessible. Although the instance methods of Object are defined by the Kernel module, we have chosen to document them here for clarity.

In the descriptions of Object’s methods, the parameter symbol refers to a symbol, which is either a quoted string or a Symbol (such as :name).

Constants
ARGF
ARGV
DATA
ENV
ENV
FALSE
MatchingData
NIL
PLATFORM
RELEASE_DATE
RUBY_PATCHLEVEL
RUBY_PLATFORM
RUBY_RELEASE_DATE
RUBY_VERSION
STDERR
STDIN	constants to hold original stdin/stdout/stderr
STDOUT
TOPLEVEL_BINDING
TRUE
VERSION	obsolete constants

Public Methods
==	Equality—At the `Object` level, `==` returns `true` only if obj and other are the same object. Typically, this method is overridden in descendent classes to provide class-specific meaning.
===	Case Equality—For class `Object`, effectively the same as calling `#==`, but typically overridden by descendents to provide meaningful semantics in `case` statements.
=~	Pattern Match—Overridden by descendents (notably `Regexp` and `String`) to provide meaningful pattern-match semantics.
__id__	Document-method: object_id
__send__	Invokes the method identified by symbol, passing it any arguments specified. You can use `__send__` if the name `send` clashes with an existing method in obj.
class	Returns the class of obj, now preferred over `Object#type`, as an object’s type in Ruby is only loosely tied to that object’s class. This method must always be called with an explicit receiver, as `class` is also a reserved word in Ruby.
clone	Produces a shallow copy of obj—the instance variables of obj are copied, but not the objects they reference. Copies the frozen and tainted state of obj. See also the discussion under `Object#dup`.
display	Prints obj on the given port (default `$>`). Equivalent to:
dup	Produces a shallow copy of obj—the instance variables of obj are copied, but not the objects they reference. `dup` copies the tainted state of obj. See also the discussion under `Object#clone`. In general, `clone` and `dup` may have different semantics in descendent classes. While `clone` is used to duplicate an object, including its internal state, `dup` typically uses the class of the descendent object to create the new instance.
eql?	Equality—At the `Object` level, `==` returns `true` only if obj and other are the same object. Typically, this method is overridden in descendent classes to provide class-specific meaning.
equal?	Equality—At the `Object` level, `==` returns `true` only if obj and other are the same object. Typically, this method is overridden in descendent classes to provide class-specific meaning.
extend	Adds to obj the instance methods from each module given as a parameter.
freeze	Prevents further modifications to obj. A `TypeError` will be raised if modification is attempted. There is no way to unfreeze a frozen object. See also `Object#frozen?`.
frozen?	Returns the freeze status of obj.
hash	Generates a `Fixnum` hash value for this object. This function must have the property that `a.eql?(b)` implies `a.hash == b.hash`. The hash value is used by class `Hash`. Any hash value that exceeds the capacity of a `Fixnum` will be truncated before being used.
id	Soon-to-be deprecated version of `Object#object_id`.
inspect	Returns a string containing a human-readable representation of obj. If not overridden, uses the `to_s` method to generate the string.
instance_eval	Evaluates a string containing Ruby source code, or the given block, within the context of the receiver (obj). In order to set the context, the variable `self` is set to obj while the code is executing, giving the code access to obj’s instance variables. In the version of `instance_eval` that takes a `String`, the optional second and third parameters supply a filename and starting line number that are used when reporting compilation errors.
instance_of?	Returns `true` if obj is an instance of the given class. See also `Object#kind_of?`.
instance_variable_defined?	Returns `true` if the given instance variable is defined in obj.
instance_variable_get	Returns the value of the given instance variable, or nil if the instance variable is not set. The `@` part of the variable name should be included for regular instance variables. Throws a `NameError` exception if the supplied symbol is not valid as an instance variable name.
instance_variable_set	Sets the instance variable names by symbol to object, thereby frustrating the efforts of the class’s author to attempt to provide proper encapsulation. The variable did not have to exist prior to this call.
instance_variables	Returns an array of instance variable names for the receiver. Note that simply defining an accessor does not create the corresponding instance variable.
is_a?	Returns `true` if class is the class of obj, or if class is one of the superclasses of obj or modules included in obj.
kind_of?	Returns `true` if class is the class of obj, or if class is one of the superclasses of obj or modules included in obj.
method	Looks up the named method as a receiver in obj, returning a `Method` object (or raising `NameError`). The `Method` object acts as a closure in obj’s object instance, so instance variables and the value of `self` remain available.
methods	Returns a list of the names of methods publicly accessible in obj. This will include all the methods accessible in obj’s ancestors.
new	Not documented
nil?	call_seq:
object_id	Returns an integer identifier for obj. The same number will be returned on all calls to `id` for a given object, and no two active objects will share an id. `Object#object_id` is a different concept from the `:name` notation, which returns the symbol id of `name`. Replaces the deprecated `Object#id`.
private_methods	Returns the list of private methods accessible to obj. If the all parameter is set to `false`, only those methods in the receiver will be listed.
protected_methods	Returns the list of protected methods accessible to obj. If the all parameter is set to `false`, only those methods in the receiver will be listed.
public_methods	Returns the list of public methods accessible to obj. If the all parameter is set to `false`, only those methods in the receiver will be listed.
remove_instance_variable	Removes the named instance variable from obj, returning that variable’s value.
respond_to?	Returns `true`> if obj responds to the given method. Private methods are included in the search only if the optional second parameter evaluates to `true`.
send	Invokes the method identified by symbol, passing it any arguments specified. You can use `__send__` if the name `send` clashes with an existing method in obj.
singleton_method_added	Invoked as a callback whenever a singleton method is added to the receiver.
singleton_method_removed	Invoked as a callback whenever a singleton method is removed from the receiver.
singleton_method_undefined	Invoked as a callback whenever a singleton method is undefined in the receiver.
singleton_methods	Returns an array of the names of singleton methods for obj. If the optional all parameter is true, the list will include methods in modules included in obj.
taint	Marks obj as tainted—if the `$SAFE` level is set appropriately, many method calls which might alter the running programs environment will refuse to accept tainted strings.
tainted?	Returns `true` if the object is tainted.
to_a	Returns an array representation of obj. For objects of class `Object` and others that don’t explicitly override the method, the return value is an array containing `self`. However, this latter behavior will soon be obsolete.
to_s	Returns a string representing obj. The default `to_s` prints the object’s class and an encoding of the object id. As a special case, the top-level object that is the initial execution context of Ruby programs returns ``main.’‘
type	Deprecated synonym for `Object#class`.
untaint	Removes the taint from obj.

Object

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