Re: Variables in for loop (style issue)

James Dennett wrote:
  > Thorsten Ottosen wrote:

  >>struct Foo
  >>{
  >> const std::vector<int>& bar() const;
  >>};
  >>
  >>In Java, C# and D you can't do it without breaking encapsulation or
  >>without copying the entire collection before returning a handle.
  >
  >
  > The idiom in Java is to return a wrapper object, which provides
  > an immutable interface and holds a reference to the underlying
  > (mutable) collection.
  >
  > C++'s built-in support for restricting access to only the
  > non-mutating part of an interface is a more direct solution,
  > but as Java shows, a similar effect can be accomplished in
  > a more cumbersome way with more basic features.
  >
  > (Java's version is also much weaker in that, if memory serves,
  > the immutable wrappers actually implement interfaces which
  > provide mutator functions, and checking is done at runtime;
  > one more way in which type-safety provided at compile-time
  > by C++ is deferred to runtime in more dynamic languages.)

I don't know if I will call this an idiom or a hack. I've have not seen
it used very much the places I have worked, because it is just too much
work.

-Thorsten

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