If i don't use @n but use n instead, there is no error

ruby-talk
1

in an instance method, if i didn't use @n but used n, the program still
runs...
and it is not changing the global n... so what is it changing?

Example:

n = 10

class Foo

  def initialize(i)
    @n = i
  end

  def change()
    puts
    puts "Inside of change!!!!!!!!!!!!!!!!"
    n = 111111 # intentionally not using @n
  end

  def print_it
    puts
    p "Printing Object"
    p @n
  end

end

foo = Foo.new(3)
foo.print_it

foo.change
foo.print_it

puts
p "Global var"
p n
-------- output ----------------------------------------------------------

C:\rails\depot>ruby test_class01.rb

"Printing Object"
3

Inside of change!!!!!!!!!!!!!!!!

"Printing Object"
3

"Global var"
10

2

kendear wrote:

in an instance method, if i didn't use @n but used n, the program still
runs...
and it is not changing the global n... so what is it changing?

Example:

n = 10

class Foo

  def initialize(i)
    @n = i
  end

  def change()
    puts
    puts "Inside of change!!!!!!!!!!!!!!!!"
    n = 111111 # intentionally not using @n
  end

  def print_it
    puts
    p "Printing Object"
    p @n
  end

end

foo = Foo.new(3)
foo.print_it

foo.change
foo.print_it

puts
p "Global var"
p n
-------- output ----------------------------------------------------------

C:\rails\depot>ruby test_class01.rb

"Printing Object"
3

Inside of change!!!!!!!!!!!!!!!!

"Printing Object"
3

"Global var"
10

well if oyou would like global n you should use $n, for me this kode looks good and proper, change method changes local variable n, not global one

3

kendear wrote:

in an instance method, if i didn't use @n but used n, the program still
runs...
and it is not changing the global n... so what is it changing?

The variable 'n' local to the current context, which is the method
'change' => the variable disappear as soon as the code exists change().

Lionel