Accessing ruby variables in nested objects -

i have gem working on. in executable parses config file , instantiates couple of objects. 1 of these objects instantiates number of "handler" objects. parsing config file array, config, settings within not accessible in of other objects. needed in handlers. when try use them, variable not exist.

i understand variable scope issue. not sure need make these accessible throughout entire program (including sub/nested objects) , not initial executable. while each of objects in program within module, actions in executable not.

constants global, live in namespace in defined.

if define config in main context, global @ root-level. if define in class or module, must refer full name outside of context.

for example:

class foo   config = file.read(...) end  config # => error, not defined foo::config # => defined 

it's bad form reference constants name, run against grain of proper object-oriented design. such, if define constants, should used internally only, , exposed via methods sub-classes can redefine or patch required.

a better example:

class foo   config = file.read(...)    def self.config     config   end end  foo.config # => configuration 

this simple abstraction important because sub-class can re-define configuration:

class bar < foo   def self.config     # ... different implementation   end end  bar.config # => different result 

even better avoid constants altogether , lazy-load things required:

class foo   def self.config     @config ||= file.read(...)   end end  foo.config # => configuration 

constants best reserved things not change, separator = ':', it's not possible or practical reconfigure them without breaking lot of code.

where have that's read in external source, might vary based on configuration or preference, it's more convenient have method intermediates this.