constantize

Tries to find a constant with the name specified in the argument string.

'Module'.constantize     # => Module
'Test::Unit'.constantize # => Test::Unit

The name is assumed to be the one of a top-level constant, no matter whether it starts with â::â or not. No lexical context is taken into account:

C = 'outside'
module M
  C = 'inside'
  C               # => 'inside'
  'C'.constantize # => 'outside', same as ::C
end

NameError is raised when the name is not in CamelCase or the constant is unknown.