What does ::MyClass Ruby scope operator do?
在Ruby中， ::MyClass/MyModule作用域操作符是做什么的，它的目的是什么？
This explicitly refers to the MyClass in the global scope. If there is a MyClass in the global scope, but also a MyClass inside of SomeModule, referring to MyClass from inside of SomeModule will refer to MyClass inside of the module, not the global MyClass. Saying ::MyClass explicitly refers to the MyClass in the global scope.
class MyClass
def self.something
puts "Global MyClass"
end
end
module SomeModule
class MyClass
def self.something
puts "SomeModule::MyClass"
end
end
print "From the module: "
MyClass.something
print "Explicitly using global scope: "
::MyClass.something
end
print "From the global scope: "
MyClass.something
print "Explicitly using module scope: "
SomeModule::MyClass.something
"global scope" just means the constant is defined on the Object class. So ::SomeModule is shorthand for Object::SomeModule
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