Here's the code:
class Something
attr_accessor :x
def initialize(x)
@x = x
end
def get_x
x
end
end
something = Something.new(5)
something.get_x # => 5
Why interpreter returns 5 if x is just a local variable in get_x method? Thanks
x is also a method. attr_accessor :x adds x= and x to your class. So, get_x is calling the x method, and returning the value for @x. see http://www.rubyist.net/~slagell/ruby/accessors.html for details.
attr_accessor :x adds two methods for you:
def x=(val)
@x = val
end
def x
@x
end
So you don't actually need get_x getter if you've added attr_accessor method.
UPD
So the question is
class Something
attr_accessor :x
def initialize(x)
@x = x
end
def set_x=(new)
x = new
end
end
Why won't x = new call default x setter: because default x setter is an instance method so you can call it for an object (Something instance) but not in your class like you try.
attr_accessor is just a "helper" it creates two methods for you, but you are free to create as much as you need
def x; "method"; end; p x; x = 42; p x. The first x invokes the method (because no local variable with that name exists), but the second identical x reads the local variable. Local variables mask methods in the same scope unless you prefix with self.The attr_accessor defines a method x (and the setter x=) which gets called in get_x.
>> something.methods.grep /^x/
=> [:x, :x=]
