Ruby language basics
- Ruby in 20 minutes
- the Ruby REPL is
irb - expressions in a string are escaped with
"#{expression}" - print function is
puts - functions are defined like:
def myfun(somearg = "default") # do something with somearg end - arguments can have default value
- functions can be called like:
myfun myfun() myfun "some other arg" myfun("some other arg") - classes are defined like:
class MyClass attr_accessor :somearg def initialize(somearg = "default") @somearg = somearg end # do something with @somearg anywhere in the class end - class instantiation is done with the "new" keyword:
myclass = MyClass.new("some other arg") - the instance variable
@someargis private - the methods defined in the class are public by default
- the attribute accessor
:someargallows to get and set the instance variable (public). Usage:myclass.someargandmyclass.somearg= "something new" - information about a class can be retrieved with
MyClass.instance_methods(show_inherited = true) - See more on Ruby-Doc
- iterations
- for each loop
@names.each do |name| puts "Hello #{name}!" end - conditionals
- if-else block
def say_bye if @names.nil? puts "..." elsif @names.respond_to?("join") # Join the list elements with commas puts "Goodbye #{@names.join(", ")}. Come back soon!" else puts "Goodbye #{@names}. Come back soon!" end end
- @/@@ vs. self
- method visibility
- variables vs constants
- ! (aka. bang) in method names means danger
- ? is indicating a boolean return type
Ruby on Rails basics
- Getting started with Ruby on Rails explains the project structure
- ActiveRecord Basics explains that
- anything that subclasses ApplicationRecord is mapped to a database table
- validations are a thing of ApplicationRecord. See more here.
- ActiveRecord Migrations explains how database migrations are done
rspec testing framework basics
...coming up...in the meantime here are some resources:
- https://dev.to/hanachin/how-to-minimize-rspec-describecontext-nesting-4179
- http://www.betterspecs.org/
- https://stackoverflow.com/questions/5359558/when-to-use-rspec-let
My IDE choice
- VSCode with extensions:
- Ruby
- Ruby Solargraph
- ruby-rubocop
- lourenci.go-to-spec
