Slides

Types and Conversions

Ref. WGR Chapter 7, Built-in essentials

Built-in Types

  • Numbers
    • 42 (Fixnum)
    • 3.14159 (Float)
  • Booleans
    • true
    • false
  • Strings
    • "apple"
    • 'banana'
  • Symbols
    • :apple

Built-in Types (cont.)

  • Regular Expressions
    • /fo*/i
  • Arrays
    • ["apple", "banana"]
  • Ranges
    • (1..10)
  • Hashes
    • {:apple => 'red', :banana => 'yellow'}
    • {apple: 'red', banana: 'yellow'}

to_*

  • to_i converts to integer
  • to_f converts to float
  • to_s converts to string
  • to_a converts to array
  • to_sym converts to symbol

to_s

  • it's tempting to use to_s in your UI
  • usually to_s is insufficient and therefore useless
  • make a custom named method instead for your purposes
    • e.g. display_name

inspect

  • inspect produces a debug-ready representation of the object
  • usually contains lots of information
  • not to be shown to users, but good in log files or console
  • a better way to debug: the "d" method