Function object
In Ruby, several objects can be considered function objects, in particular Method and Proc objects. Ruby also has two kinds of objects that can be thought of as semi-function objects: UnboundMethod and block. UnboundMethods must first be bound to an object (thus becoming a Method) before they can be used as a function object. Blocks can be called like function objects, but to be used in any other capacity as an object (e.g. passed as an argument) they must first be converted to a Proc. More recently, symbols (accessed via the literal unary indicator codice_35) can also be converted to codice_36s. Using Ruby's unary codice_37 operator—equivalent to calling codice_38 on an object, and assuming that method exists—the Ruby Extensions Project created a simple hack.
Anonymous function
In R the anonymous functions are defined using the syntax codice_87 .
Ruby supports anonymous functions by using a syntactical structure called "block". There are two data types for blocks in Ruby. codice_88s behave similarly to closures, whereas codice_89s behave more analogous to an anonymous function. When passed to a method, a block is converted into a Proc in some circumstances.