A generator that wraps expressions passed to it in the specified extension wrapper.  
 More...
template<template< typename > class Extends>
struct boost::proto::generator< Extends >
A generator that wraps expressions passed to it in the specified extension wrapper. 
Generators are intended for use as the first template parameter to the domain<> class template and control if and how expressions within that domain are to be customized. generator<> wraps each expression passed to it in the Extends<> wrapper.