2012-05-08-1 CPlusPlus11

Last edit

Summary: test

Changed:

< test

to

> = Changes to old habits - you need to move to!
> With moving available the old habit of always passing non native types as const to ref is not necessary any more. Moving makes call by value and return by value good alternatives.
> From my experience return by value was something that was used a lot although the overhead of a copy. Partly because functions are easier to understand that way, return values in parameters is not taught as a good design, and partly because of the return value optimization sometimes got away without a copy anyway and still do!
> With C++11 we can safely use call by value when we want that even for complex types. So we should write code like this from now on:
> {{{
> string manipulate(string s)
> {
> <... perform some manipulation on s ...>
> return s;
> }
> }}}
> Since we are going to change the value on the string we might as well use call by value and change that. The modified value is then returned. The move ctor will kick in an see to that no unnecessary copy is needed.


Changes to old habits - you need to move to!

With moving available the old habit of always passing non native types as const to ref is not necessary any more. Moving makes call by value and return by value good alternatives.

From my experience return by value was something that was used a lot although the overhead of a copy. Partly because functions are easier to understand that way, return values in parameters is not taught as a good design, and partly because of the return value optimization sometimes got away without a copy anyway and still do!

With C++11 we can safely use call by value when we want that even for complex types. So we should write code like this from now on:

   string manipulate(string s)
   {
      <... perform some manipulation on s ...>
      return s;
   }

Since we are going to change the value on the string we might as well use call by value and change that. The modified value is then returned. The move ctor will kick in an see to that no unnecessary copy is needed.