Conventions Flashcards
Which case/format should Classes be in?
CamelCased
Print all the words in docs.words
docs.words.each { |word| puts word }
Which case/format should methods, arguments and variables be in?
snake_cased
What is a better way to write the following:
if not @read_only
unless @read_only
What is a better way to write the following:
while ! document_is_printed?
until document.printed?
One liner to conditionally set @title to new_title only if document.read_only? is not true from inside the document.
@title = new_title unless read_only?
How does ruby treat booleans?
Only false or nil are treated as false.
Everything else is true.
How would you initialize a variable only if the variable is nil?
@variable ||= ‘’
What is a shortcut for creating an array of strings?
array_of_strings = %w{California Florida Ohio}
#=> ["California", "Florida", "Ohio"]How can you create a hash? Give 2 ways.
- { first_name: ‘Russ’, last_name: ‘Olsen’ }
2. Hash.new(first_name: ‘Russ’, last_name: ‘Olsen’)
How would you make a method that takes an arbitrary set of arguments?
def some_method( args )
How do multiple arguments get parsed when using a splat?
They are passed in as an array
What is the shortcut for passing a hash as an argument?
load_font( :name => ‘times roman’, :size => 12)
or
load_font :name => ‘times roman’, :size => 12
How would you use an each block to access data in a hash?
movies.each { |name, value| puts “#{name} => #{value}” }
How is .map different from .each?
.map creates a new array containing everything that the block returns
It is useful for transforming the contents of a collection en masse
What does .inject do?
Every time it calls the block, it replaces the current result with the return value of the previous call to the block. It returns the result as its return value when it runs out of elements.
How would you run a method in place on an object rather than returning a new object? (For many methods, not all)
Add a bang to the method (Example: a.reverse! )
