Dissapearing data from array

[Noé Alejandro]

Hi all.

I have the next problem.

a = %w(a b)
z = %w(1)
a.insert(1, z)
puts a
a
1
b

z.clear
puts a
a
b

Oopss... where "1" is? what happened? what can I do to keep "1" when I
clear the array (z)?

Thanks a lot.

 

[Florian Gilcher]

Hi all.
=20
I have the next problem.
=20
a =3D %w(a b)
z =3D %w(1)
a.insert(1, z)
puts a
a
1
b

Try=20

puts a.inspect
#=3D> ["a", ["1"], "b"]

=20
z.clear
puts a
a
b

puts a.inspect
#=3D> ["a", [], "b"]

=20
Oopss... where "1" is? what happened? what can I do to keep "1" when I
clear the array (z)?

Ruby uses references. So a.insert(1, z) inserts a reference to z at =
position 1 in the array. So once you clear z, it will be cleared =
noticed by everyone referring to it - a, in this case.

Regards,
Florian=

 

[Andrea Dallera]

From what i've understood your aim is to "detach" the reference of the
inserted element from the original one. That can be done with z.clone,
in your example it will look like this:

a = %w(a b)
z = %w(1)
a.insert(1, z.clone)
z.clear
puts a
a
1
b

 

[Noé Alejandro]

Thanks guys... Florian for your explanation, Andrea for your solution.
Now I understand what happens and how to solve it.