gauthamchandra/learning-ruby-from-js

Notes for programming in ruby if you are coming in from a different programming language like JS

Learning Ruby from a JavaScript background

This is purely a compilation of helpful notes for devs who are coming in to Ruby from JavaScript. Although the notes are tailored for a JavaScript developer, it could be useful for others.

Please file an issue or a pull request if you see any inconsistencies or errors!

Topics:

It is highly recommended that beginners move through these in the proposed order.

1. Pure Basics and Primitive Types
2. Blocks, Procs, Lambdas and Functions - Everything to do with introducing Blocks, Procs, Lambdas and Functions and some techniques to pass data and control between them.
3. Control Statements and Looping - Looping is introduced along with control statements like if and unless
4. OOP in Ruby - Inheritence and Classes, Modules and information hiding
5. Some basic coding conventions - Some very basic practices to keep in mind when coding in Ruby.

More to come soon!

learning-ruby-from-js's Issues

For loop in ruby vs js

Hey just wanted to point out that a for x in (0..100) in Ruby is not the same as for (let x...) loop. The difference is in the ability to increment x in JS but not Ruby:

// javascript
for (let i = 0; i < 100; i++) {
  console.log(i)
  i += 3
}
// => prints 0, 4, 8, 12...

# ruby
for i in (0..100)
  p i
  i += 3
end
# => prints 0 to 100

Minor correction

Using the yield keyword you can invoke code blocks and pass it arguments as if they were functions. Unless the blocks are specified as arguments, they are outside the parentheses. See below:

def foo(greeting)
	puts 'Inside the function foo'
	yield(greeting)
	puts 'Back inside the function foo'
end
foo("Top of the mornin to ya!") { |greeting| puts "#{greeting} John" }

Expected

Inside the function foo
Top of the mornin to ya! John
Back inside the function foo

Actual

Inside the function foo
Top of the mornin to ya John
Back inside the function foo

You could change

foo("Top of the mornin to ya!") { |greeting| puts "#{greeting} John" }

to

foo("Top of the mornin to ya") { |greeting| puts "#{greeting} John" }