Const Correct Is Encapsulation

EditHint: Move stuff on this topic from ConstCorrectness to here.

I appreciate ConstCorrectness enormously and miss it sorely in JavaLanguage. :-(

Some languages have RunTime constantness, with freeze and thaw. Do they allow thaw when running in a secure mode? Do freeze and thaw act on the object or the object reference?


Given...

   Object nonConst; 
   Object const Const; 
   Object const & constRef = nonConst; 

nonConst.foo(); // <-- calls foo() (non-const) if available Const.foo(); // <-- must call foo() const constRef.foo(); // <-- must call foo() const
...note that constancy is a form of encapsulation. Both the Const object and the constRef make their Object more encapsulated - meaning potentially safer and more robust - than the non-constant versions. So "const-correct" code generally extends more usages to constant things than to changeable things.


More literally:

 interface FooConst?{
	int readX();
	int readY();
 }
 abstract class Foo implements FooConst?{
	abstract public int readX(); 
	abstract public int readY(); 
	abstract public int writeX(int value); 
	abstract public int writeY(int value); 
 }

Methods that want a "const Foo" parameter need only declare a FooConst? as their argument.

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