13-01-2022

continuing with classes

Initialize is run at object's instantiation of class x

def and class are scope gates

def or class are different scopes

thus, each variable has its own specific scope

variables within a specific scope cannot be accesed beyond that scope

• there are regular variables
• constants
• method variables, named after the class
• instance variables like @name, @colour, etc

variable scope defines what other objects can see ( and interact ) with them

instance variables

• only exist within the class definition
• @hanger is local to the blueprint only, and can be used within method

local variables

• exist in the main process
• exists in conditional branches
• HOWEVER if the object is instantiated in a non-executed conditional branch, the object will not exist later
  • the programme will recognise the name, but its value will be set to nil
  • ( is this like declaring variables at the start in C, but never using them)

in ruby ranges (1..5) is inclusive, whilst (1...5) excludes final number

class self.methods

class def self.method allow you to access the class without instantiating the object

rememeber to instantiate an object!!