Variables

Purpose

Variables have a name and store a value. This value can be a number, symbol, or list.

Usage

When a variable is evaluated, it returns its value.

Variables are usually created using the "define" function. Define requires two arguments: the name of the variable, and the value of the variable. The value argument is evaluated before it is assigned to the name.

Examples

Creating variables:

  ox --> (define name 'Matt)
  Matt
  ox --> (define frameNumber 100)
  100

Two variables, "name" and "frameNumber" have been created. They both have been assigned values:

  ox --> name
  Matt
  ox --> frameNumber
  100

Once defined, variables can be used in expressions:

  ox --> (define a 1)
  1
  ox --> (define b 2)
  2
  ox --> (+ a b) 
  3

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