How to disable warning for redefining a constant when loading a file

Question

Is there a way to disable warning: already initialized constant when loading particular files?

Answer 1

The solution to your problem depends on what is causing it.

1 - You are changing the value of a constant that was set before somewhere in your code, or are trying to define a constant with the same name as an existant class or module. Solution: don't use constants if you know in advance that the value of the constant will change; don't define constants with the same name as class/modules.

2 - You are in a situation where you want to redefine a constant for good reasons, without getting warnings. There are two options.

First, you could undefine the constant before redefining it (this requires a helper method, because remove_const is a private function):

Object.module_eval do   # Unset a constant without private access.   def self.const_unset(const)     self.instance_eval { remove_const(const) }   end end 

Or, you could just tell the Ruby interpreter to shut up (this suppresses all warnings):

# Runs a block of code without warnings. def silence_warnings(&block)   warn_level = $VERBOSE   $VERBOSE = nil   result = block.call   $VERBOSE = warn_level   result end 

3 - You are requiring an external library that defines a class/module whose name clashes with a new constant or class/module you are creating. Solution: wrap your code inside a top-level module-namespace to prevent the name clash.

class SomeClass; end module SomeModule    SomeClass = '...'  end 

4 - Same as above, but you absolutely need to define a class with the same name as the gem/library's class. Solution: you can assign the library's class name to a variable, and then clear it for your later use:

require 'clashing_library' some_class_alias = SomeClass SomeClass = nil # You can now define your own class: class SomeClass; end # Or your own constant: SomeClass = 'foo' 

Answer 2

Try this :

Kernel::silence_warnings { MY_CONSTANT = 'my value '}