Download Iteration AryList = [5,6,7,8] SndList = Array.new SndList = AryList

Iteration
AryList = [5,6,7,8]
SndList = Array.new
SndList = AryList.collect
puts b
Everything has a value
x = 88
y = 11
z = if x < y
true
else
false
end
Symbols are not lightweight Strings
:marzsexy.object_id == :marzsexy.object_id
Everything is an Object
marielouClass = Class.new do
attr_accessor :instance_var
end
Variable Constants
M_NUM = 58
Naming conventions http://itsignals.cascadia.com.au/?p=7
-Instance variables
@cust_id=id
@cust_name=name
@cust_addr=addr
-global variables
$global_variable = 10
Keyword arguments http://brainspec.com/blog/2012/10/08/keyword-arguments-ruby-2-0/
def foo(x, str: "foo", num: 424242)
[x, str, num]
end
foo(13) #=> [13, 'foo', 424242]
foo(13, str: 'bar') #=> [13, 'bar', 424242]
The universal truth
if 0
puts "0 is true"
else
puts "0 is false"
end
Prints “0 is true”
Access modifiers apply until the end of scope http://www.tutorialspoint.com/ruby/ruby_classes.htm
class Sample
def hello
puts "Hello Ruby!"
end
end
Method access http://www.tutorialspoint.com/ruby/ruby_classes.htm
class Customer
@@no_of_customers=0
def initialize(id, name, addr)
@cust_id=id
@cust_name=name
@cust_addr=addr
end
end
Classes are open http://rubylearning.com/satishtalim/ruby_open_classes.html
1. class Dog
2.
def big_bark
3.
puts 'Woof! Woof!'
4.
end
5. end
6. # make an object
7. d = Dog.new('Labrador', 'Benzy')
8. d.bark
9. d.big_bark
10. d.display
Funny method names http://rubylearning.com/satishtalim/ruby_names.html
1. rice_on_square = 1
2. 64.times do |square|
3.
puts "On square #{square + 1} are #{rice_on_square} grain(s)"
4.
rice_on_square *= 2
5. end
Singleton method http://rubymonk.com/learning/books/4-ruby-primer-ascent/chapters/39-ruby-sobject-model/lessons/131-singleton-methods-and-metaclasses
class Foo
end
foo=Foo.new
def foo.shout
puts "Foo Foo Foo!"
end
foo.shout
p Foo.new.respond_to?(:shout)
Missing methods http://rubylearning.com/satishtalim/ruby_method_missing.html
1. class Dummy
2.
def method_missing(m, *args, &block)
3.
puts "There's no method called #{m} here -- please try again."
4.
end
5. end
6. Dummy.new.anything
Message passing, not function calls
# This
3 + 9
# Is the same as this ...
3.+(9)
# Which is the same as this:
3.send "+", 9
Blocks are Objects, they just don’t know it yet http://www.tutorialspoint.com/ruby/ruby_blocks.htm
def test(&block)
block.call
end
test { puts "Hello World!"}
Operators are syntactic sugar http://rubymonk.com/learning/books/1-ruby-primer/chapters/6objects/lessons/37-syntactic-sugar-for-special-methods
words = ["foo", "bar", "baz"]
words[1]