Boost C++ Libraries

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Struct display_expr

boost::proto::functional::display_expr — Pretty-print a Proto expression tree.

Synopsis

// In header: <boost/proto/debug.hpp>


struct display_expr {
  // types
  typedef void result_type;

  // construct/copy/destruct
  display_expr(std::ostream & = std::cout, int = 0);

  // public member functions
  template<typename Expr> void operator()(Expr const &) const;
};

Description

A PolymorphicFunctionObject which accepts a Proto expression tree and pretty-prints it to an ostream for debugging purposes.

`display_expr` public construct/copy/destruct

display_expr(std::ostream & sout = std::cout, int depth = 0);

Parameters:

`depth`	The starting indentation depth for this node. Children nodes will be displayed at a starting depth of `depth+4`.
`sout`	The `ostream` to which the expression tree will be written.

`display_expr` public member functions

template<typename Expr> void operator()(Expr const & expr) const;