October 2015’s edition of Overload includes an excellent article by Andrew Sutton on Concepts for C++. I first heard about Concepts at the ACCU 2013 conference and it’s exciting to hear that they have reached Technical Specification stage.
There’s no doubt in my mind that concepts will play a huge role for those involved in generic programming. In F#, we already have the ability to state constraints on template arguments e.g. to ensure that ‘T satisfies the comparison constraint:
type Container<'T when 'T : comparison>( items : 'T[] ) =
// ...
However, I wasn’t expecting the ability to use concepts for placeholders (so that, once you’ve defined a concept, you can use it where you might have used auto to gain the benefits of type deduction without the loss of information).
musingstudio 