How do you pass arguments in Ruby?
In your Ruby programs, you can access any command-line arguments passed by the shell with the ARGV special variable. ARGV is an Array variable which holds, as strings, each argument passed by the shell.
What does * args mean in Ruby?
In the code you posted, *args simply indicates that the method accepts a variable number of arguments in an array called args . It could have been called anything you want (following the Ruby naming rules, of course).
How do you comment in Ruby?
The Ruby single-line comment begins with the # character and ends at the end of the line. Any characters from the # character to the end of the line are completely ignored by the Ruby interpreter. The # character doesn’t necessarily have to occur at the beginning of the line; it can occur anywhere.
What is splat in Ruby?
Splat operator or start (*) arguments in Ruby define they way they are received to a variable. Single splat operator can be used to receive arguments as an array to a variable or destructure an array into arguments. Double splat operator can be used to destructure a hash.
What is slice in Ruby?
#slice is a method that operates on arrays, strings, and (since Ruby 2.5. 0) hashes. We’ll just focus on arrays for now, since the logic is basically the same regardless, but keep in mind that you can call #slice on strings and hashes as well. #slice allows you to cut into an array and select specific elements.
What is &Block in Ruby?
The &block is a way of sending a piece of Ruby code in to a method and then evaluating that code in the scope of that method. In your example code above it means a partial named cart will be rendered in a div.
What is .call in Ruby?
call method is to invoke/execute a Proc/Method instance. The example below might make it more clear. m = 12.method(“+”) # => `method` gets the `+` method defined in the `Fixnum` instance # m.class # => Method m.call(3) #=> 15 # `3` is passed inside the `+` method as argument m.call(20) #=> 32.
What is Attr_accessor in Ruby?
In Ruby, object methods are public by default, while data is private. … attr_accessor is a shortcut method when you need both attr_reader and attr_writer . Since both reading and writing data are common, the idiomatic method attr_accessor is quite useful.
How does yield work in Ruby?
We can send a block to our method and it can call that block multiple times. When yield is called in side a method then method requires a block with in it. … A block is simply a chunk of code, and yield allows us to inject that code at some place into a method.
What is send method in Ruby?
Ruby Language Metaprogramming send() method
send() is used to pass message to object . send() is an instance method of the Object class. The first argument in send() is the message that you’re sending to the object – that is, the name of a method. It could be string or symbol but symbols are preferred.
How do you comment out large sections of code in Ruby?
Multi Line or Block Ruby Comments
Multiple lines of text or code can be defined as comments using the Ruby =begin and =end comment markers. These are known as the comment block markers.
How do you comment out code in Ruby on Rails?
As the other answers said, use to comment within a Rails view.
What are magic comments in Ruby?
A magic comment changes the behavior of the Ruby interpreter in some way. For example: The frozen_string_literals comment will make your strings frozen by default. Another magic comment allows you to change the file’s encoding.