Ruby weak 1

gistfile1.md

Please visit new wiki for more info and tasks!

Ruby 1

• ruby style => OOP everywhere, e.g. 2 + 2 is a call Fixnum(2).+(Fixnum(2))
• [1,2,3].each {|n| puts n}
• Simple classes (Fixnum, String, Float)
• Kernel (puts, gets, p)
• Simple expressions ("a" + "b", 1 + 5, etc)
• variables (x = 10)
• Loops ( 1.upto(5) {|i| puts i}, 5.times do puts "Hey"; end)
• Cast (1.to_s, 2.to_f, 10.0.to_i)
• Constants and CamelCase
• String literals and string interpolation: puts "#{x} + #{y} = #{x+y}"
• String substitution

puts "foo bar".sub('foo', 'bar')

• Regular Expressions and scan

"This is a string".scan(/\w/) {|s| puts s}

• Matching and capturing

Ruby 2

• Arrays
• Hashes
• Code blocks
• Symbols
• Methods with blocks, with argument list, hash as last argument
• Time
• Extending a Fixnum with cool methods for Time (Time.now + 5.hours)
• Fixnum -> Bignum

Examples for methods with blocks:

# simple function that puts "Hello" and invoke a block passed to it
def helloBlock(&b)
 puts "Hello"
 yield
end

helloBlock { puts "Yay" }
# => Hello
#    Yay

# lets store a block and invoke it several times
x = lambda {|a,b| puts a+b }

x.call(1,2)
# => 3
x.call("abc","def")
# => abcdef

def sayHelloWithBlock(name, &b)
 5.times do
  yield name
 end
end

sayHelloWithBlock("Mirsaid") {|name| puts "Hello #{name}!" }

# method with *args
def say(*words)
 puts words.join(' ')
end

say "Ruby", "is", "awesome", "!"

# method with hash as last argument
def whatDoYouThinkAbout(hash = {})
 if hash[:pronoun].nil?
  puts "I think that #{hash[:language]} #{hash[:opinion]}.."
 else
  puts "I think that #{hash[:language]} #{hash[:pronoun]} #{hash[:opinion]}.."
 end
end

whatDoYouThinkAbout :language => "PHP", :opinion => "Sucks"
# => I think that PHP - sucks

whatDoYouThinkAbout :language => "C", :pronoun => "is", :opinion => "prolix"
# => I think that C is prolix 

whatDoYouThinkAbout :language => "Ruby", :pronoun => "is", :opinion => "cool"
# => I think that Ruby is cool

x = [1,2,3] + [4,5,6]
x.each { |elem| puts elem.to_s + " is cool!" }

%w{don't you think that ruby is cool?}.each_with_index do |word, index|
 if index == 0
  print "#{word.capitalize} "
 else
  print "#{word} "
 end
end

References and Documentation

Ruby 1

• Kernel: http://ruby-doc.org/core-2.2.1/Kernel.html
• String: http://ruby-doc.org/core-2.2.1/String.html
• Reg Exp: http://ruby-doc.org/core-2.2.1/Regexp.html
• RegEx editor: http://rubular.com/
• Wiki: http://en.wikipedia.org/wiki/Regular_expression
• Wiki-ru: https://ru.wikipedia.org/wiki/%D0%A0%D0%B5%D0%B3%D1%83%D0%BB%D1%8F%D1%80%D0%BD%D1%8B%D0%B5_%D0%B2%D1%8B%D1%80%D0%B0%D0%B6%D0%B5%D0%BD%D0%B8%D1%8F

Ruby 2

• About Constructs:
• http://www.tutorialspoint.com/ruby/ruby_if_else.htm
• http://www.tutorialspoint.com/ruby/ruby_loops.htm
• Array: http://ruby-doc.org/core-2.2.1/Array.html
• Hash: http://ruby-doc.org/core-2.2.1/Hash.html
• Time: http://ruby-doc.org/core-2.2.1/Time.html
• Ranage: http://ruby-doc.org/core-2.2.1/Range.html
• Symbol: http://ruby-doc.org/core-2.2.1/Symbol.html

About Blocks: http://www.reactive.io/tips/2008/12/21/understanding-ruby-blocks-procs-and-lambdas/

CamelCase: https://ru.wikipedia.org/wiki/CamelCase