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/*
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* Created: 27-01-2016
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* Modified: Wed 27 Jan 2016 17:57:28 CET
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* Author: Jonas R. Glesaaen (jonas@glesaaen.com)
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*/
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#include<iostream>
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#include<utility>
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#include<boost/type_index.hpp>
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//Simple names for the operators
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struct plus {};
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struct minus {};
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struct times {};
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struct divide {};
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//Base expression used to only need a single
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//operator overload for every operator
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template <typename Expr>
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struct base_expr {};
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//A binary expression storing an operator and the
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//two expressions on either side
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template <typename Op, typename Le, typename Re>
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struct binary_expr : base_expr<binary_expr<Op,Le,Re>> {};
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//A leaf class
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struct val : base_expr<val> {};
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//Operator that does nothing, only builds the expression tree
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//Trailing return type not really needed, mostly for a cleaner syntax
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template <typename Le, typename Re>
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auto operator+(base_expr<Le>, base_expr<Re>)
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-> binary_expr<plus,Le,Re>
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{
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return {};
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}
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template <typename Le, typename Re>
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auto operator-(base_expr<Le>, base_expr<Re>)
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-> binary_expr<minus,Le,Re>
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{
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return {};
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}
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template <typename Le, typename Re>
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auto operator*(base_expr<Le>, base_expr<Re>)
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-> binary_expr<times,Le,Re>
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{
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return {};
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}
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template <typename Le, typename Re>
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auto operator/(base_expr<Le>, base_expr<Re>)
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-> binary_expr<divide,Le,Re>
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{
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return {};
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}
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//Prints out the expression tree of an arbitrary expression
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int main(int, char**)
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{
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val v;
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std::cout << boost::typeindex::type_id<decltype(v + v - v*v/(v+v))>().pretty_name() << std::endl;
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}
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