CMPUT174 Lecture Notes - Lecture 4: Unary Operation, Parsing, Lexical Analysis

• School: University of Alberta
• Department: Computing Science
• Course: CMPUT174

Document Summary

To access an object in memory, a python program need to reference that object. Literals, identifiers and some keywords can be used to reference objects. Each unique literal token references an object in memory with a different identity. Literal is the name we use in the program to refer to an actual object in memory. Literal is pre-bound to a specific object in memory and cannot be rebound. Each identifier in a program can either be bound to an object or can be unbound. An identifier can be bound to an object and then rebound to a different object. True, false and none are pre-bound to specific objects in memory. The bool type has only two objects for that type, each referenced by one of the keywords, A reference in a program is analogous to the name of a person name is just a name that refers to a person, it is not actually a person.