[SOLVED] What is the purpose of setting Ruby block local variables when blocks have their own scope already?

What is the purpose of setting Ruby block local variables when blocks have their own scope already?

Learning about Ruby blocks [here][1]. What is the point of having block local variable in this example:

x = 10
5.times do |y; x|
  x = y
  puts "x in inside the block: #{x}"
end
puts "x outside the block: #{x}"

x in inside the block: 0
x in inside the block: 1
x in inside the block: 2
x in inside the block: 3
x in inside the block: 4
x in outside the block: 10

When you can just do the below instead? The x in the block is already going to have its own scope, which is different than the x that is outside the block.

x = 10
5.times do |x|
  puts "x in inside the block: #{x}"
end
puts "x outside the block: #{x}"

The resulting output is the same.

Solution

Block scopes nest inside their lexically enclosing scope:

foo = :outerfoo
bar = :outerbar

1.times do |;bar|
  foo = :innerfoo
  bar = :innerbar
  baz = :innerbaz
end

foo #=> :innerfoo
bar #=> :outerbar
baz # NameError

You need a way to tell Ruby: "I don't want this variable from the outer scope, I want a fresh one." That's what block local variables do.