How to override []= array method?

Ruby
1

My class is defined as,

class Memory < Array

and I need to override the []= method.
I tried something like,

def []=(address, value)
self[address] = Word.new(value)
end

which causes an infinite loop of course: ‘stack level too deep’.
How to do it right?

2

Il giorno Fri, 20 Apr 2012 16:22:07 +0900
“Gaurav C.” [email protected] ha scritto:

which causes an infinite loop of course: ‘stack level too deep’.
How to do it right?

Before defining the new method use alias_method to create a copy of the
original one with a different name:

class Memory < Array
alias_method :set_element, :[]=

def []= address, value
set_element address, value
end
end

I hope this helps

Stefano

3

Use the super keyword. It calls the method by the same name belonging
to a class or module higher in the “inheritance hierarchy”.

(Note that “super” and “super()” have different meanings - the second
form calls the method with no arguments, while the first with the same
arguments as passed to your method.)

def []=(address, value)
super(address, Word.new(value))
end

– Matma R.

4

On Fri, Apr 20, 2012 at 9:22 AM, Gaurav C. [email protected] wrote:

My class is defined as,

class Memory < Array

Please do not do this. Rather use composition to achieve what you want.

and I need to override the []= method.

If you do it, you need to override all manipulating methods because
otherwise it is not guaranteed that all elements in the Array will be
instances of Word.

Kind regards

robert