ruby_types.md

JumpStart Live (JSL)

Day 1

Ruby Types

Overview

Everything in Ruby is an object. There are 7 data types you should know about now.

Data Type	Description	Example
String	Anything surrounded by single or double quotes	"hello", 'hello'
Integer	A number with no decimal	1, 0, -7
Float	Real value (decimal)	0.5
Array	An ordered list	[5, 0, 1]
Symbol	A named object	:apple
Hash	A set of key, value pairs	{ A: 2, B: 3, C: 1}
Range	A set of values with a beginning and an end	(2..6)

Fixnum is another name for Integer. Ruby version 2.4.0 introduced the term Integer, so if your ruby version is at least 2.4.0, use Integer. Otherwise use Fixnum. You can check your version by typing ruby --version in the terminal.

Determining the type

To determine the type of an object you can use .class

x = 1
puts x.class #Integer

word = "hello"
puts word.class #String

Resources

• Ada Ruby Types Video ~ 8min