4. Terms and definitions

For the purposes of this document, the following terms and definitions apply. Other terms are defined where they appear in bold slant face or on the left side of a syntax rule.

sequence of statements which is passed to a method invocation

object which defines the behavior of a set of other objects called its instances

NOTE The behavior is a set of methods which can be invoked on an instance.

variable whose value is shared by all the instances of a class

variable which is defined in a class or a module and is accessible outside the class or module

NOTE The value of a constant is regularly expected to remain constant during the execution of a program, but Ruby does not force it. In some implementations, an assignment to a constant which already exists causes a warning, but this document does not specifity it.

special class which defines a behavior for only a single object

object which represents an unexpected event

variable which is accessible everywhere in a Ruby program

possibly differing between implementations, but defined for every implementation

possibly differing between implementations, and not necessarily defined for any particular implementation

method which can be invoked on all the instances of a class

variable which belongs to a single object

variable which is accessible only in a certain scope introduced by a program construct such as a method definition, a block, a class definition, a module definition, an eigenclass definition, or the toplevel of a program

procedure which, when invoked on an object, performs a set of computations on the object

attribute of a method which determines the conditions on which a method invocation is allowed

object which provides features to be included into a class or another module

computational entity which has a state and a behavior

instance method of the eigenclass of an object

computational entity which stores a reference to an object