mirror of
https://github.com/jbranchaud/til
synced 2026-01-03 15:18:01 +00:00
31 lines
563 B
Markdown
31 lines
563 B
Markdown
# Listing Local Variables
|
|
|
|
In Ruby 2.2, the `binding` object gives us access to a method
|
|
`#local_variables` which returns the symbol names of the binding's local
|
|
variables. We can see this in action with
|
|
|
|
```ruby
|
|
def square(x)
|
|
puts binding.local_variables.inspect
|
|
x.times do |a|
|
|
puts binding.local_variables.inspect
|
|
end
|
|
z = x * x
|
|
puts binding.local_variables.inspect
|
|
z
|
|
end
|
|
square(2)
|
|
```
|
|
|
|
which results in
|
|
|
|
```ruby
|
|
[:x, :z]
|
|
[:a, :x, :z]
|
|
[:a, :x, :z]
|
|
[:x, :z]
|
|
=> 4
|
|
```
|
|
|
|
[source](http://ruby-doc.org/core-2.2.0/Binding.html#method-i-local_variables)
|