On Fri, 19 Jun 2009, Martin D Kealey wrote: > To that end I would propose that: > - parameters should be read-only AND invariant by default, and > - that invariance should be enforced passing a deep immutable clone > (*5) in place of any object that isn't already immutable.
Sorry, typo: that last word should have been "invariant", meaning that it *won't* change, rather than "immutable", meaning that it *can't*. Compilers can rely on invariance to perform a range of very powerful optimizations; immutability is one way to guarantee invariance, but not the only way. -Martin
